51736561 has 4 divisors (see below), whose sum is σ = 51905392. Its totient is φ = 51567732.

The previous prime is 51736507. The next prime is 51736579. The reversal of 51736561 is 16563715.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51736561 - 2¹¹ = 51734513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51739561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 83955 + ... + 84568.

It is an arithmetic number, because the mean of its divisors is an integer number (12976348).

Almost surely, 2^51736561 is an apocalyptic number.

It is an amenable number.

51736561 is a deficient number, since it is larger than the sum of its proper divisors (168831).

51736561 is a wasteful number, since it uses less digits than its factorization.

51736561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168830.

The product of its digits is 18900, while the sum is 34.

The square root of 51736561 is about 7192.8131492484. The cubic root of 51736561 is about 372.6197347923.

The spelling of 51736561 in words is "fifty-one million, seven hundred thirty-six thousand, five hundred sixty-one".