1517707421 has 2 divisors, whose sum is σ = 1517707422. Its totient is φ = 1517707420.

The previous prime is 1517707397. The next prime is 1517707423. The reversal of 1517707421 is 1247077151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1384881796 + 132825625 = 37214^2 + 11525^2 .

It is a cyclic number.

It is not a de Polignac number, because 1517707421 - 2⁶ = 1517707357 is a prime.

Together with 1517707423, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1517707423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 758853710 + 758853711.

It is an arithmetic number, because the mean of its divisors is an integer number (758853711).

Almost surely, 2^1517707421 is an apocalyptic number.

It is an amenable number.

1517707421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1517707421 is an equidigital number, since it uses as much as digits as its factorization.

1517707421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13720, while the sum is 35.

The square root of 1517707421 is about 38957.7645790926. The cubic root of 1517707421 is about 1149.2010634849.

The spelling of 1517707421 in words is "one billion, five hundred seventeen million, seven hundred seven thousand, four hundred twenty-one".