121318649856 has 416 divisors, whose sum is σ = 383787011520. Its totient is φ = 37739298816.

The previous prime is 121318649801. The next prime is 121318649857. The reversal of 121318649856 is 658946813121.

It is a happy number.

121318649856 is a `hidden beast` number, since 1 + 21 + 3 + 1 + 86 + 498 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (121318649857) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 325250886 + ... + 325251258.

Almost surely, 2^121318649856 is an apocalyptic number.

121318649856 is a gapful number since it is divisible by the number (16) 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 121318649856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (191893505760).

121318649856 is an abundant number, since it is smaller than the sum of its proper divisors (262468361664).

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

121318649856 is a wasteful number, since it uses less digits than its factorization.

121318649856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 596 (or 568 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

The spelling of 121318649856 in words is "one hundred twenty-one billion, three hundred eighteen million, six hundred forty-nine thousand, eight hundred fifty-six".