51447731 has 4 divisors (see below), whose sum is σ = 51463512. Its totient is φ = 51431952.

The previous prime is 51447719. The next prime is 51447749. The reversal of 51447731 is 13774415.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13774415 = 5 ⋅2754883.

It is a cyclic number.

It is not a de Polignac number, because 51447731 - 2⁶ = 51447667 is a prime.

It is a super-2 number, since 2×51447731² = 5293738050096722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51447791) 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, 986 + ... + 10191.

It is an arithmetic number, because the mean of its divisors is an integer number (12865878).

Almost surely, 2^51447731 is an apocalyptic number.

51447731 is a deficient number, since it is larger than the sum of its proper divisors (15781).

51447731 is a wasteful number, since it uses less digits than its factorization.

51447731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15780.

The product of its digits is 11760, while the sum is 32.

The square root of 51447731 is about 7172.7073689089. The cubic root of 51447731 is about 371.9250316227.

The spelling of 51447731 in words is "fifty-one million, four hundred forty-seven thousand, seven hundred thirty-one".