1211618880 has 336 divisors, whose sum is σ = 4420136448. Its totient is φ = 304128000.

The previous prime is 1211618879. The next prime is 1211618893. The reversal of 1211618880 is 888161121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 47 ways as a sum of consecutive naturals, for example, 3660315 + ... + 3660645.

It is an arithmetic number, because the mean of its divisors is an integer number (13155168).

Almost surely, 2^1211618880 is an apocalyptic number.

1211618880 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 1211618880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2210068224).

1211618880 is an abundant number, since it is smaller than the sum of its proper divisors (3208517568).

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

1211618880 is a wasteful number, since it uses less digits than its factorization.

1211618880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 36.

The square root of 1211618880 is about 34808.3162477015. The cubic root of 1211618880 is about 1066.0772542270.

The spelling of 1211618880 in words is "one billion, two hundred eleven million, six hundred eighteen thousand, eight hundred eighty".