61649864 has 16 divisors (see below), whose sum is σ = 116505600. Its totient is φ = 30581712.

The previous prime is 61649857. The next prime is 61649879. The reversal of 61649864 is 46894616.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29324 + ... + 31355.

It is an arithmetic number, because the mean of its divisors is an integer number (7281600).

Almost surely, 2^61649864 is an apocalyptic number.

It is an amenable number.

61649864 is a deficient number, since it is larger than the sum of its proper divisors (54855736).

61649864 is a wasteful number, since it uses less digits than its factorization.

61649864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60812 (or 60808 counting only the distinct ones).

The product of its digits is 248832, while the sum is 44.

The square root of 61649864 is about 7851.7427364885. The cubic root of 61649864 is about 395.0427000787.

The spelling of 61649864 in words is "sixty-one million, six hundred forty-nine thousand, eight hundred sixty-four".