121399980625 has 135 divisors (see below), whose sum is σ = 195047629623. Its totient is φ = 75259800000.

The previous prime is 121399980623. The next prime is 121399980631. The reversal of 121399980625 is 526089993121.

The square root of 121399980625 is 348425.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 117567380161 + 3832600464 = 342881^2 + 61908^2 .

It is not a de Polignac number, because 121399980625 - 2¹ = 121399980623 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is not an unprimeable number, because it can be changed into a prime (121399980623) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 670718035 + ... + 670718215.

Almost surely, 2^121399980625 is an apocalyptic number.

121399980625 is the 348425-th square number.

121399980625 is the 174213-rd centered octagonal number.

It is an amenable number.

121399980625 is a deficient number, since it is larger than the sum of its proper divisors (73647648998).

121399980625 is an frugal number, since it uses more digits than its factorization.

121399980625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 55.

The spelling of 121399980625 in words is "one hundred twenty-one billion, three hundred ninety-nine million, nine hundred eighty thousand, six hundred twenty-five".