51440402 has 16 divisors (see below), whose sum is σ = 87984792. Its totient is φ = 22344960.

The previous prime is 51440393. The next prime is 51440437. The reversal of 51440402 is 20404415.

It can be written as a sum of positive squares in 4 ways, for example, as 51136801 + 303601 = 7151^2 + 551^2 .

It is a super-2 number, since 2×51440402² = 5292229915843208, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 57749 + ... + 58632.

Almost surely, 2^51440402 is an apocalyptic number.

51440402 is a deficient number, since it is larger than the sum of its proper divisors (36544390).

51440402 is a wasteful number, since it uses less digits than its factorization.

51440402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116413.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 51440402 is about 7172.1964557589. The cubic root of 51440402 is about 371.9073698914.

Adding to 51440402 its reverse (20404415), we get a palindrome (71844817).

The spelling of 51440402 in words is "fifty-one million, four hundred forty thousand, four hundred two".