51981759 has 6 divisors (see below), whose sum is σ = 75084776. Its totient is φ = 34654500.

The previous prime is 51981751. The next prime is 51981791. The reversal of 51981759 is 95718915.

51981759 is a `hidden beast` number, since 519 + 81 + 7 + 59 = 666.

It is not a de Polignac number, because 51981759 - 2³ = 51981751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51981751) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2887867 + ... + 2887884.

Almost surely, 2^51981759 is an apocalyptic number.

51981759 is a deficient number, since it is larger than the sum of its proper divisors (23103017).

51981759 is a wasteful number, since it uses less digits than its factorization.

51981759 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5775757 (or 5775754 counting only the distinct ones).

The product of its digits is 113400, while the sum is 45.

The square root of 51981759 is about 7209.8376542055. The cubic root of 51981759 is about 373.2074665159.

The spelling of 51981759 in words is "fifty-one million, nine hundred eighty-one thousand, seven hundred fifty-nine".