51561494 has 24 divisors (see below), whose sum is σ = 80909640. Its totient is φ = 24641280.

The previous prime is 51561479. The next prime is 51561511. The reversal of 51561494 is 49416515.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 267062 + ... + 267254.

It is an arithmetic number, because the mean of its divisors is an integer number (3371235).

Almost surely, 2^51561494 is an apocalyptic number.

51561494 is a deficient number, since it is larger than the sum of its proper divisors (29348146).

51561494 is a wasteful number, since it uses less digits than its factorization.

51561494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 365 counting only the distinct ones).

The product of its digits is 21600, while the sum is 35.

The square root of 51561494 is about 7180.6332589821. The cubic root of 51561494 is about 372.1989676354.

The spelling of 51561494 in words is "fifty-one million, five hundred sixty-one thousand, four hundred ninety-four".