121255553531 has 4 divisors (see below), whose sum is σ = 138577775472. Its totient is φ = 103933331592.

The previous prime is 121255553513. The next prime is 121255553563. The reversal of 121255553531 is 135355552121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121255553531 is a prime.

It is a super-2 number, since 2×121255553531² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121255553431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8661110960 + ... + 8661110973.

It is an arithmetic number, because the mean of its divisors is an integer number (34644443868).

Almost surely, 2^121255553531 is an apocalyptic number.

121255553531 is a deficient number, since it is larger than the sum of its proper divisors (17322221941).

121255553531 is an equidigital number, since it uses as much as digits as its factorization.

121255553531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17322221940.

The product of its digits is 112500, while the sum is 38.

The spelling of 121255553531 in words is "one hundred twenty-one billion, two hundred fifty-five million, five hundred fifty-three thousand, five hundred thirty-one".