2615981 has 2 divisors, whose sum is σ = 2615982. Its totient is φ = 2615980.

The previous prime is 2615971. The next prime is 2615983. The reversal of 2615981 is 1895162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1713481 + 902500 = 1309^2 + 950^2 .

It is a cyclic number.

It is not a de Polignac number, because 2615981 - 2⁶ = 2615917 is a prime.

It is a super-2 number, since 2×2615981² = 13686713184722, which contains 22 as substring.

Together with 2615983, 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 (2615983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1307990 + 1307991.

It is an arithmetic number, because the mean of its divisors is an integer number (1307991).

2^2615981 is an apocalyptic number.

It is an amenable number.

2615981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2615981 is an equidigital number, since it uses as much as digits as its factorization.

2615981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 32.

The square root of 2615981 is about 1617.3994559168. The cubic root of 2615981 is about 137.7880419040.

The spelling of 2615981 in words is "two million, six hundred fifteen thousand, nine hundred eighty-one".