1217982690 has 64 divisors (see below), whose sum is σ = 3255390720. Its totient is φ = 324051840.

The previous prime is 1217982683. The next prime is 1217982709. The reversal of 1217982690 is 962897121.

1217982690 is a nontrivial binomial coefficient, being equal to C(49356, 2).

It is a super-2 number, since 2×1217982690² = 2966963666279272200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 118455 + ... + 128325.

It is an arithmetic number, because the mean of its divisors is an integer number (50865480).

Almost surely, 2^1217982690 is an apocalyptic number.

1217982690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1217982690 is the 49355-th triangular number and also the 24678-th hexagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1217982690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1627695360).

1217982690 is an abundant number, since it is smaller than the sum of its proper divisors (2037408030).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1217982690 is a wasteful number, since it uses less digits than its factorization.

1217982690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10344 (or 10338 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 1217982690 is about 34899.6087370618. The cubic root of 1217982690 is about 1067.9404555870.

The spelling of 1217982690 in words is "one billion, two hundred seventeen million, nine hundred eighty-two thousand, six hundred ninety".