51323391 has 48 divisors (see below), whose sum is σ = 90552384. Its totient is φ = 27343872.

The previous prime is 51323353. The next prime is 51323399. The reversal of 51323391 is 19332315.

It is a happy number.

It is not a de Polignac number, because 51323391 - 2⁷ = 51323263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51323399) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 185145 + ... + 185421.

It is an arithmetic number, because the mean of its divisors is an integer number (1886508).

Almost surely, 2^51323391 is an apocalyptic number.

51323391 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

51323391 is a deficient number, since it is larger than the sum of its proper divisors (39228993).

51323391 is a wasteful number, since it uses less digits than its factorization.

51323391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480 (or 477 counting only the distinct ones).

The product of its digits is 2430, while the sum is 27.

The square root of 51323391 is about 7164.0345476554. The cubic root of 51323391 is about 371.6251644042.

The spelling of 51323391 in words is "fifty-one million, three hundred twenty-three thousand, three hundred ninety-one".