521970641 has 4 divisors (see below), whose sum is σ = 549442800. Its totient is φ = 494498484.

The previous prime is 521970637. The next prime is 521970643. The reversal of 521970641 is 146079125.

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 521970641 - 2² = 521970637 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521970643) 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, 13736051 + ... + 13736088.

It is an arithmetic number, because the mean of its divisors is an integer number (137360700).

Almost surely, 2^521970641 is an apocalyptic number.

It is an amenable number.

521970641 is a deficient number, since it is larger than the sum of its proper divisors (27472159).

521970641 is a wasteful number, since it uses less digits than its factorization.

521970641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27472158.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 521970641 is about 22846.6768042969. The cubic root of 521970641 is about 805.1596926092.

The spelling of 521970641 in words is "five hundred twenty-one million, nine hundred seventy thousand, six hundred forty-one".