51698644 has 12 divisors (see below), whose sum is σ = 90527668. Its totient is φ = 25833600.

The previous prime is 51698609. The next prime is 51698701. The reversal of 51698644 is 44689615.

It can be written as a sum of positive squares in 2 ways, for example, as 24010000 + 27688644 = 4900^2 + 5262^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51698644.

It is a congruent number.

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, 6604 + ... + 12124.

Almost surely, 2^51698644 is an apocalyptic number.

It is an amenable number.

51698644 is a deficient number, since it is larger than the sum of its proper divisors (38829024).

51698644 is a wasteful number, since it uses less digits than its factorization.

51698644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7866 (or 7864 counting only the distinct ones).

The product of its digits is 207360, while the sum is 43.

The square root of 51698644 is about 7190.1769102019. The cubic root of 51698644 is about 372.5286832859.

The spelling of 51698644 in words is "fifty-one million, six hundred ninety-eight thousand, six hundred forty-four".