521379551 has 40 divisors (see below), whose sum is σ = 699129600. Its totient is φ = 384516720.

The previous prime is 521379541. The next prime is 521379557. The reversal of 521379551 is 155973125.

Added to its reverse (155973125) it gives a square (677352676 = 26026²).

It is not a de Polignac number, because 521379551 - 2²² = 517185247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521379557) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 501290 + ... + 502328.

It is an arithmetic number, because the mean of its divisors is an integer number (17478240).

Almost surely, 2^521379551 is an apocalyptic number.

521379551 is a deficient number, since it is larger than the sum of its proper divisors (177750049).

521379551 is a wasteful number, since it uses less digits than its factorization.

521379551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097 (or 1076 counting only the distinct ones).

The product of its digits is 47250, while the sum is 38.

The square root of 521379551 is about 22833.7371229503. The cubic root of 521379551 is about 804.8556514964.

Adding to 521379551 its reverse (155973125), we get a square (677352676 = 26026²).

The spelling of 521379551 in words is "five hundred twenty-one million, three hundred seventy-nine thousand, five hundred fifty-one".