51817761 has 6 divisors (see below), whose sum is σ = 74847890. Its totient is φ = 34545168.

The previous prime is 51817757. The next prime is 51817763. The reversal of 51817761 is 16771815.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 49787136 + 2030625 = 7056^2 + 1425^2 .

It is not a de Polignac number, because 51817761 - 2² = 51817757 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51817763) 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, 2878756 + ... + 2878773.

Almost surely, 2^51817761 is an apocalyptic number.

It is an amenable number.

51817761 is a deficient number, since it is larger than the sum of its proper divisors (23030129).

51817761 is a wasteful number, since it uses less digits than its factorization.

51817761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5757535 (or 5757532 counting only the distinct ones).

The product of its digits is 11760, while the sum is 36.

The square root of 51817761 is about 7198.4554593329. The cubic root of 51817761 is about 372.8145738414.

The spelling of 51817761 in words is "fifty-one million, eight hundred seventeen thousand, seven hundred sixty-one".