1211613920 has 192 divisors, whose sum is σ = 3292047360. Its totient is φ = 417331200.

The previous prime is 1211613901. The next prime is 1211613943. The reversal of 1211613920 is 293161121.

It is a super-2 number, since 2×1211613920² = 2936016582275532800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1211613920.

It is a congruent number.

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, 2891471 + ... + 2891889.

It is an arithmetic number, because the mean of its divisors is an integer number (17146080).

Almost surely, 2^1211613920 is an apocalyptic number.

1211613920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211613920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1646023680).

1211613920 is an abundant number, since it is smaller than the sum of its proper divisors (2080433440).

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

1211613920 is a wasteful number, since it uses less digits than its factorization.

1211613920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 521 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 1211613920 is about 34808.2450002869. The cubic root of 1211613920 is about 1066.0757994928.

The spelling of 1211613920 in words is "one billion, two hundred eleven million, six hundred thirteen thousand, nine hundred twenty".