61538144 has 24 divisors (see below), whose sum is σ = 121451400. Its totient is φ = 30693376.

The previous prime is 61538143. The next prime is 61538159. The reversal of 61538144 is 44183516.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a self number, because there is not a number n which added to its sum of digits gives 61538144.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61538143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12227 + ... + 16509.

It is an arithmetic number, because the mean of its divisors is an integer number (5060475).

Almost surely, 2^61538144 is an apocalyptic number.

It is an amenable number.

61538144 is a deficient number, since it is larger than the sum of its proper divisors (59913256).

61538144 is a wasteful number, since it uses less digits than its factorization.

61538144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4742 (or 4734 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 61538144 is about 7844.6251663161. The cubic root of 61538144 is about 394.8039276846.

The spelling of 61538144 in words is "sixty-one million, five hundred thirty-eight thousand, one hundred forty-four".