51358491 has 24 divisors (see below), whose sum is σ = 75675600. Its totient is φ = 33558336.

The previous prime is 51358487. The next prime is 51358499. The reversal of 51358491 is 19485315.

51358491 is a `hidden beast` number, since 513 + 58 + 4 + 91 = 666.

It is not a de Polignac number, because 51358491 - 2² = 51358487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51358499) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 146985 + ... + 147333.

It is an arithmetic number, because the mean of its divisors is an integer number (3153150).

Almost surely, 2^51358491 is an apocalyptic number.

51358491 is a deficient number, since it is larger than the sum of its proper divisors (24317109).

51358491 is a wasteful number, since it uses less digits than its factorization.

51358491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635 (or 632 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 51358491 is about 7166.4838658857. The cubic root of 51358491 is about 371.7098630867.

The spelling of 51358491 in words is "fifty-one million, three hundred fifty-eight thousand, four hundred ninety-one".