51721413 has 8 divisors (see below), whose sum is σ = 71340000. Its totient is φ = 33291888.

The previous prime is 51721409. The next prime is 51721421. The reversal of 51721413 is 31412715.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51721413 - 2² = 51721409 is a prime.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 297163 + ... + 297336.

It is an arithmetic number, because the mean of its divisors is an integer number (8917500).

Almost surely, 2^51721413 is an apocalyptic number.

It is an amenable number.

51721413 is a deficient number, since it is larger than the sum of its proper divisors (19618587).

51721413 is a wasteful number, since it uses less digits than its factorization.

51721413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594531.

The product of its digits is 840, while the sum is 24.

The square root of 51721413 is about 7191.7600766433. The cubic root of 51721413 is about 372.5833646729.

The spelling of 51721413 in words is "fifty-one million, seven hundred twenty-one thousand, four hundred thirteen".