51291420 has 48 divisors (see below), whose sum is σ = 144281760. Its totient is φ = 13614336.

The previous prime is 51291419. The next prime is 51291433. The reversal of 51291420 is 2419215.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11874 + ... + 15606.

It is an arithmetic number, because the mean of its divisors is an integer number (3005870).

Almost surely, 2^51291420 is an apocalyptic number.

It is an amenable number.

51291420 is an abundant number, since it is smaller than the sum of its proper divisors (92990340).

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

51291420 is a wasteful number, since it uses less digits than its factorization.

51291420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3974 (or 3972 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 51291420 is about 7161.8028456528. The cubic root of 51291420 is about 371.5479825980.

The spelling of 51291420 in words is "fifty-one million, two hundred ninety-one thousand, four hundred twenty".