121897725825 has 48 divisors (see below), whose sum is σ = 202472951616. Its totient is φ = 64711046400.

The previous prime is 121897725799. The next prime is 121897725827. The reversal of 121897725825 is 528527798121.

It is not a de Polignac number, because 121897725825 - 2¹⁹ = 121897201537 is a prime.

It is a super-2 number, since 2×121897725825² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (121897725827) 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 47 ways as a sum of consecutive naturals, for example, 16802899 + ... + 16810151.

It is an arithmetic number, because the mean of its divisors is an integer number (4218186492).

Almost surely, 2^121897725825 is an apocalyptic number.

121897725825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121897725825 is a deficient number, since it is larger than the sum of its proper divisors (80575225791).

121897725825 is a wasteful number, since it uses less digits than its factorization.

121897725825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8274 (or 8269 counting only the distinct ones).

The product of its digits is 5644800, while the sum is 57.

The spelling of 121897725825 in words is "one hundred twenty-one billion, eight hundred ninety-seven million, seven hundred twenty-five thousand, eight hundred twenty-five".