513404921 has 2 divisors, whose sum is σ = 513404922. Its totient is φ = 513404920.

The previous prime is 513404887. The next prime is 513404929. The reversal of 513404921 is 129404315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 340771600 + 172633321 = 18460^2 + 13139^2 .

It is a cyclic number.

It is not a de Polignac number, because 513404921 - 2²² = 509210617 is a prime.

It is a super-2 number, since 2×513404921² = 527169225814032482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (513404929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256702460 + 256702461.

It is an arithmetic number, because the mean of its divisors is an integer number (256702461).

Almost surely, 2^513404921 is an apocalyptic number.

It is an amenable number.

513404921 is a deficient number, since it is larger than the sum of its proper divisors (1).

513404921 is an equidigital number, since it uses as much as digits as its factorization.

513404921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 513404921 is about 22658.4403920482. The cubic root of 513404921 is about 800.7310614205.

The spelling of 513404921 in words is "five hundred thirteen million, four hundred four thousand, nine hundred twenty-one".