1521981713 has 8 divisors (see below), whose sum is σ = 1739778432. Its totient is φ = 1304277696.

The previous prime is 1521981647. The next prime is 1521981767. The reversal of 1521981713 is 3171891251.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1521981713 - 2¹² = 1521977617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1521981793) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16556 + ... + 57602.

It is an arithmetic number, because the mean of its divisors is an integer number (217472304).

Almost surely, 2^1521981713 is an apocalyptic number.

It is an amenable number.

1521981713 is a deficient number, since it is larger than the sum of its proper divisors (217796719).

1521981713 is an equidigital number, since it uses as much as digits as its factorization.

1521981713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46351.

The product of its digits is 15120, while the sum is 38.

The square root of 1521981713 is about 39012.5840338730. The cubic root of 1521981713 is about 1150.2788770418.

The spelling of 1521981713 in words is "one billion, five hundred twenty-one million, nine hundred eighty-one thousand, seven hundred thirteen".