61638375 has 64 divisors (see below), whose sum is σ = 111121920. Its totient is φ = 30240000.

The previous prime is 61638371. The next prime is 61638383. The reversal of 61638375 is 57383616.

It is not a de Polignac number, because 61638375 - 2² = 61638371 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61638371) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 292020 + ... + 292230.

It is an arithmetic number, because the mean of its divisors is an integer number (1736280).

Almost surely, 2^61638375 is an apocalyptic number.

61638375 is a deficient number, since it is larger than the sum of its proper divisors (49483545).

61638375 is a wasteful number, since it uses less digits than its factorization.

61638375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289 (or 279 counting only the distinct ones).

The product of its digits is 90720, while the sum is 39.

The square root of 61638375 is about 7851.0110813831. The cubic root of 61638375 is about 395.0181586482.

The spelling of 61638375 in words is "sixty-one million, six hundred thirty-eight thousand, three hundred seventy-five".