51031420 has 24 divisors (see below), whose sum is σ = 116908848. Its totient is φ = 18556800.

The previous prime is 51031391. The next prime is 51031423. The reversal of 51031420 is 2413015.

It is a junction number, because it is equal to n+sod(n) for n = 51031394 and 51031403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51031423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115761 + ... + 116200.

It is an arithmetic number, because the mean of its divisors is an integer number (4871202).

Almost surely, 2^51031420 is an apocalyptic number.

It is an amenable number.

51031420 is an abundant number, since it is smaller than the sum of its proper divisors (65877428).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51031420 is a wasteful number, since it uses less digits than its factorization.

51031420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231981 (or 231979 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 51031420 is about 7143.6279298407. The cubic root of 51031420 is about 370.9191174124.

Adding to 51031420 its reverse (2413015), we get a palindrome (53444435).

The spelling of 51031420 in words is "fifty-one million, thirty-one thousand, four hundred twenty".