121872135825 has 36 divisors (see below), whose sum is σ = 238130772048. Its totient is φ = 59089519200.

The previous prime is 121872135821. The next prime is 121872135829. The reversal of 121872135825 is 528531278121.

It is an interprime number because it is at equal distance from previous prime (121872135821) and next prime (121872135829).

It is not a de Polignac number, because 121872135825 - 2² = 121872135821 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (121872135821) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 24618159 + ... + 24623108.

It is an arithmetic number, because the mean of its divisors is an integer number (6614743668).

Almost surely, 2^121872135825 is an apocalyptic number.

121872135825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121872135825 is a deficient number, since it is larger than the sum of its proper divisors (116258636223).

121872135825 is a wasteful number, since it uses less digits than its factorization.

121872135825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49241294 (or 49241286 counting only the distinct ones).

The product of its digits is 268800, while the sum is 45.

The spelling of 121872135825 in words is "one hundred twenty-one billion, eight hundred seventy-two million, one hundred thirty-five thousand, eight hundred twenty-five".