51031431 has 16 divisors (see below), whose sum is σ = 82475520. Its totient is φ = 30927960.

The previous prime is 51031423. The next prime is 51031439. The reversal of 51031431 is 13413015.

51031431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51031423) and next prime (51031439).

It is not a de Polignac number, because 51031431 - 2³ = 51031423 is a prime.

It is a super-2 number, since 2×51031431² = 5208413899815522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51031439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85615 + ... + 86208.

It is an arithmetic number, because the mean of its divisors is an integer number (5154720).

Almost surely, 2^51031431 is an apocalyptic number.

51031431 is a deficient number, since it is larger than the sum of its proper divisors (31444089).

51031431 is a wasteful number, since it uses less digits than its factorization.

51031431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171843 (or 171837 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 51031431 is about 7143.6286997576. The cubic root of 51031431 is about 370.9191440634.

Adding to 51031431 its reverse (13413015), we get a palindrome (64444446).

The spelling of 51031431 in words is "fifty-one million, thirty-one thousand, four hundred thirty-one".