51440265 has 40 divisors (see below), whose sum is σ = 92913480. Its totient is φ = 27226368.

The previous prime is 51440251. The next prime is 51440273. The reversal of 51440265 is 56204415.

It can be written as a sum of positive squares in 4 ways, for example, as 8982009 + 42458256 = 2997^2 + 6516^2 .

It is not a de Polignac number, because 51440265 - 2⁸ = 51440009 is a prime.

It is a super-2 number, since 2×51440265² = 5292201726540450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 63181 + ... + 63989.

It is an arithmetic number, because the mean of its divisors is an integer number (2322837).

Almost surely, 2^51440265 is an apocalyptic number.

It is an amenable number.

51440265 is a deficient number, since it is larger than the sum of its proper divisors (41473215).

51440265 is a wasteful number, since it uses less digits than its factorization.

51440265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 983 (or 974 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 51440265 is about 7172.1869049823. The cubic root of 51440265 is about 371.9070397270.

The spelling of 51440265 in words is "fifty-one million, four hundred forty thousand, two hundred sixty-five".