521398667790 has 1152 divisors, whose sum is σ = 2005530928128. Its totient is φ = 93924126720.

The previous prime is 521398667761. The next prime is 521398667791. The reversal of 521398667790 is 97766893125.

521398667790 is a `hidden beast` number, since 521 + 39 + 8 + 6 + 6 + 7 + 79 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521398667791) by changing a digit.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 1116485137 + ... + 1116485603.

It is an arithmetic number, because the mean of its divisors is an integer number (1740912264).

Almost surely, 2^521398667790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521398667790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1002765464064).

521398667790 is an abundant number, since it is smaller than the sum of its proper divisors (1484132260338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

521398667790 is a wasteful number, since it uses less digits than its factorization.

521398667790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546 (or 525 counting only the distinct ones).

The product of its (nonzero) digits is 34292160, while the sum is 63.

The spelling of 521398667790 in words is "five hundred twenty-one billion, three hundred ninety-eight million, six hundred sixty-seven thousand, seven hundred ninety".