521661794 has 8 divisors (see below), whose sum is σ = 782672220. Its totient is φ = 260771056.

The previous prime is 521661787. The next prime is 521661797. The reversal of 521661794 is 497166125.

It can be written as a sum of positive squares in 2 ways, for example, as 521528569 + 133225 = 22837^2 + 365^2 .

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

It is not an unprimeable number, because it can be changed into a prime (521661797) 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, 18089 + ... + 37020.

Almost surely, 2^521661794 is an apocalyptic number.

521661794 is a deficient number, since it is larger than the sum of its proper divisors (261010426).

521661794 is a wasteful number, since it uses less digits than its factorization.

521661794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59844.

The product of its digits is 90720, while the sum is 41.

The square root of 521661794 is about 22839.9166811090. The cubic root of 521661794 is about 805.0008585051. Note that the first 3 decimals are identical.

The spelling of 521661794 in words is "five hundred twenty-one million, six hundred sixty-one thousand, seven hundred ninety-four".