51821275 has 36 divisors (see below), whose sum is σ = 72696736. Its totient is φ = 36590400.

The previous prime is 51821239. The next prime is 51821309. The reversal of 51821275 is 57212815.

It is not a de Polignac number, because 51821275 - 2⁹ = 51820763 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 111694 + ... + 112156.

Almost surely, 2^51821275 is an apocalyptic number.

51821275 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51821275 is a deficient number, since it is larger than the sum of its proper divisors (20875461).

51821275 is a wasteful number, since it uses less digits than its factorization.

51821275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532 (or 516 counting only the distinct ones).

The product of its digits is 5600, while the sum is 31.

The square root of 51821275 is about 7198.6995353328. The cubic root of 51821275 is about 372.8230010729.

The spelling of 51821275 in words is "fifty-one million, eight hundred twenty-one thousand, two hundred seventy-five".