1521394499 has 2 divisors, whose sum is σ = 1521394500. Its totient is φ = 1521394498.

The previous prime is 1521394493. The next prime is 1521394541. The reversal of 1521394499 is 9944931251.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1521394499 - 2²⁰ = 1520345923 is a prime.

It is a super-2 number, since 2×1521394499² = 4629282443174922002, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1521394493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 760697249 + 760697250.

It is an arithmetic number, because the mean of its divisors is an integer number (760697250).

Almost surely, 2^1521394499 is an apocalyptic number.

1521394499 is a deficient number, since it is larger than the sum of its proper divisors (1).

1521394499 is an equidigital number, since it uses as much as digits as its factorization.

1521394499 is an evil number, because the sum of its binary digits is even.

The product of its digits is 349920, while the sum is 47.

The square root of 1521394499 is about 39005.0573515794. The cubic root of 1521394499 is about 1150.1309237205.

The spelling of 1521394499 in words is "one billion, five hundred twenty-one million, three hundred ninety-four thousand, four hundred ninety-nine".