121651936560 has 800 divisors, whose sum is σ = 528909004800. Its totient is φ = 25175992320.

The previous prime is 121651936493. The next prime is 121651936591. The reversal of 121651936560 is 65639156121.

121651936560 is a `hidden beast` number, since 1 + 2 + 1 + 6 + 51 + 9 + 36 + 560 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 239001586 + ... + 239002094.

It is an arithmetic number, because the mean of its divisors is an integer number (661136256).

Almost surely, 2^121651936560 is an apocalyptic number.

121651936560 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 121651936560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264454502400).

121651936560 is an abundant number, since it is smaller than the sum of its proper divisors (407257068240).

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

121651936560 is a wasteful number, since it uses less digits than its factorization.

121651936560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1031 (or 1016 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The spelling of 121651936560 in words is "one hundred twenty-one billion, six hundred fifty-one million, nine hundred thirty-six thousand, five hundred sixty".