25791621 has 16 divisors (see below), whose sum is σ = 34978944. Its totient is φ = 16902144.

The previous prime is 25791613. The next prime is 25791629. The reversal of 25791621 is 12619752.

It is an interprime number because it is at equal distance from previous prime (25791613) and next prime (25791629).

It is not a de Polignac number, because 25791621 - 2³ = 25791613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25791629) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76365 + ... + 76701.

It is an arithmetic number, because the mean of its divisors is an integer number (2186184).

Almost surely, 2^25791621 is an apocalyptic number.

It is an amenable number.

25791621 is a deficient number, since it is larger than the sum of its proper divisors (9187323).

25791621 is a wasteful number, since it uses less digits than its factorization.

25791621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700.

The product of its digits is 7560, while the sum is 33.

The square root of 25791621 is about 5078.5451656946. The cubic root of 25791621 is about 295.4560446071.

The spelling of 25791621 in words is "twenty-five million, seven hundred ninety-one thousand, six hundred twenty-one".