2599981 has 2 divisors, whose sum is σ = 2599982. Its totient is φ = 2599980.

The previous prime is 2599973. The next prime is 2599991. The reversal of 2599981 is 1899952.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2340900 + 259081 = 1530^2 + 509^2 .

It is a cyclic number.

It is not a de Polignac number, because 2599981 - 2³ = 2599973 is a prime.

It is a super-2 number, since 2×2599981² = 13519802400722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2599931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1299990 + 1299991.

It is an arithmetic number, because the mean of its divisors is an integer number (1299991).

2^2599981 is an apocalyptic number.

It is an amenable number.

2599981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2599981 is an equidigital number, since it uses as much as digits as its factorization.

2599981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 43.

The square root of 2599981 is about 1612.4456579991. The cubic root of 2599981 is about 137.5065517539.

The spelling of 2599981 in words is "two million, five hundred ninety-nine thousand, nine hundred eighty-one".