51721473 has 16 divisors (see below), whose sum is σ = 70638336. Its totient is φ = 33651840.

The previous prime is 51721447. The next prime is 51721487. The reversal of 51721473 is 37412715.

It is not a de Polignac number, because 51721473 - 2⁶ = 51721409 is a prime.

It is a super-2 number, since 2×51721473² = 5350221538579458, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51721473.

It is not an unprimeable number, because it can be changed into a prime (51721433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24040 + ... + 26102.

It is an arithmetic number, because the mean of its divisors is an integer number (4414896).

Almost surely, 2^51721473 is an apocalyptic number.

It is an amenable number.

51721473 is a deficient number, since it is larger than the sum of its proper divisors (18916863).

51721473 is a wasteful number, since it uses less digits than its factorization.

51721473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2264.

The product of its digits is 5880, while the sum is 30.

The square root of 51721473 is about 7191.7642480827. The cubic root of 51721473 is about 372.5835087460.

The spelling of 51721473 in words is "fifty-one million, seven hundred twenty-one thousand, four hundred seventy-three".