121565721060 has 72 divisors (see below), whose sum is σ = 421427837376. Its totient is φ = 27786450240.

The previous prime is 121565721029. The next prime is 121565721061. The reversal of 121565721060 is 60127565121.

121565721060 is a `hidden beast` number, since 1 + 2 + 15 + 6 + 572 + 10 + 60 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (121565721061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48239106 + ... + 48241625.

It is an arithmetic number, because the mean of its divisors is an integer number (5853164408).

Almost surely, 2^121565721060 is an apocalyptic number.

121565721060 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121565721060 is an abundant number, since it is smaller than the sum of its proper divisors (299862116316).

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

121565721060 is a wasteful number, since it uses less digits than its factorization.

121565721060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96480753 (or 96480748 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The spelling of 121565721060 in words is "one hundred twenty-one billion, five hundred sixty-five million, seven hundred twenty-one thousand, sixty".