51942731 has 4 divisors (see below), whose sum is σ = 52243152. Its totient is φ = 51642312.

The previous prime is 51942707. The next prime is 51942743. The reversal of 51942731 is 13724915.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51942731 - 2¹⁰ = 51941707 is a prime.

It is a super-2 number, since 2×51942731² = 5396094607476722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51942031) 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, 149951 + ... + 150296.

It is an arithmetic number, because the mean of its divisors is an integer number (13060788).

Almost surely, 2^51942731 is an apocalyptic number.

51942731 is a deficient number, since it is larger than the sum of its proper divisors (300421).

51942731 is a wasteful number, since it uses less digits than its factorization.

51942731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300420.

The product of its digits is 7560, while the sum is 32.

The square root of 51942731 is about 7207.1305663211. The cubic root of 51942731 is about 373.1140415140.

The spelling of 51942731 in words is "fifty-one million, nine hundred forty-two thousand, seven hundred thirty-one".