18394140625 has 81 divisors (see below), whose sum is σ = 27637192881. Its totient is φ = 12206250000.

The previous prime is 18394140623. The next prime is 18394140637. The reversal of 18394140625 is 52604149381.

The square root of 18394140625 is 135625.

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

It can be written as a sum of positive squares in 4 ways, for example, as 13077980881 + 5316159744 = 114359^2 + 72912^2 .

It is not a de Polignac number, because 18394140625 - 2¹ = 18394140623 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18394140623) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 593359360 + ... + 593359390.

Almost surely, 2^18394140625 is an apocalyptic number.

18394140625 is the 135625-th square number.

18394140625 is the 67813-rd centered octagonal number.

It is an amenable number.

18394140625 is a deficient number, since it is larger than the sum of its proper divisors (9243052256).

18394140625 is an frugal number, since it uses more digits than its factorization.

18394140625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116 (or 43 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 43.

The spelling of 18394140625 in words is "eighteen billion, three hundred ninety-four million, one hundred forty thousand, six hundred twenty-five".