1638629325 has 24 divisors (see below), whose sum is σ = 3010224000. Its totient is φ = 873935280.

The previous prime is 1638629309. The next prime is 1638629339. The reversal of 1638629325 is 5239268361.

1638629325 is a `hidden beast` number, since 1 + 638 + 6 + 2 + 9 + 3 + 2 + 5 = 666.

It is not a de Polignac number, because 1638629325 - 2⁴ = 1638629309 is a prime.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1213125 + ... + 1214474.

It is an arithmetic number, because the mean of its divisors is an integer number (125426000).

Almost surely, 2^1638629325 is an apocalyptic number.

1638629325 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1638629325 is a deficient number, since it is larger than the sum of its proper divisors (1371594675).

1638629325 is a wasteful number, since it uses less digits than its factorization.

1638629325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2427618 (or 2427607 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 1638629325 is about 40479.9867218358. The cubic root of 1638629325 is about 1178.9450796371.

The spelling of 1638629325 in words is "one billion, six hundred thirty-eight million, six hundred twenty-nine thousand, three hundred twenty-five".