522551721 has 4 divisors (see below), whose sum is σ = 696735632. Its totient is φ = 348367812.

The previous prime is 522551713. The next prime is 522551723. The reversal of 522551721 is 127155225.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 522551721 - 2³ = 522551713 is a prime.

It is a super-2 number, since 2×522551721² = 546120602240123682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (522551723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87091951 + ... + 87091956.

It is an arithmetic number, because the mean of its divisors is an integer number (174183908).

Almost surely, 2^522551721 is an apocalyptic number.

It is an amenable number.

522551721 is a deficient number, since it is larger than the sum of its proper divisors (174183911).

522551721 is a wasteful number, since it uses less digits than its factorization.

522551721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174183910.

The product of its digits is 7000, while the sum is 30.

The square root of 522551721 is about 22859.3902149642. The cubic root of 522551721 is about 805.4583611869.

The spelling of 522551721 in words is "five hundred twenty-two million, five hundred fifty-one thousand, seven hundred twenty-one".