1015260721 has 2 divisors, whose sum is σ = 1015260722. Its totient is φ = 1015260720.

The previous prime is 1015260661. The next prime is 1015260749. The reversal of 1015260721 is 1270625101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 992565025 + 22695696 = 31505^2 + 4764^2 .

It is a cyclic number.

It is not a de Polignac number, because 1015260721 - 2⁷ = 1015260593 is a prime.

It is not a weakly prime, because it can be changed into another prime (1015260751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 507630360 + 507630361.

It is an arithmetic number, because the mean of its divisors is an integer number (507630361).

Almost surely, 2^1015260721 is an apocalyptic number.

It is an amenable number.

1015260721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1015260721 is an equidigital number, since it uses as much as digits as its factorization.

1015260721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 1015260721 is about 31863.1561682141. The cubic root of 1015260721 is about 1005.0612475565.

Adding to 1015260721 its reverse (1270625101), we get a palindrome (2285885822).

The spelling of 1015260721 in words is "one billion, fifteen million, two hundred sixty thousand, seven hundred twenty-one".