2597513981 has 4 divisors (see below), whose sum is σ = 2617342464. Its totient is φ = 2577685500.

The previous prime is 2597513969. The next prime is 2597514001. The reversal of 2597513981 is 1893157952.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2597513981 - 2¹⁸ = 2597251837 is a prime.

It is a super-2 number, since 2×2597513981² = 13494157762980936722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2597513951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9914045 + ... + 9914306.

It is an arithmetic number, because the mean of its divisors is an integer number (654335616).

Almost surely, 2^2597513981 is an apocalyptic number.

It is an amenable number.

2597513981 is a deficient number, since it is larger than the sum of its proper divisors (19828483).

2597513981 is a wasteful number, since it uses less digits than its factorization.

2597513981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19828482.

The product of its digits is 680400, while the sum is 50.

The square root of 2597513981 is about 50965.8118840463. The cubic root of 2597513981 is about 1374.6304648385.

The spelling of 2597513981 in words is "two billion, five hundred ninety-seven million, five hundred thirteen thousand, nine hundred eighty-one".