25787621 has 2 divisors, whose sum is σ = 25787622. Its totient is φ = 25787620.

The previous prime is 25787611. The next prime is 25787653. The reversal of 25787621 is 12678752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23716900 + 2070721 = 4870^2 + 1439^2 .

It is a cyclic number.

It is not a de Polignac number, because 25787621 - 2¹⁸ = 25525477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25787611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12893810 + 12893811.

It is an arithmetic number, because the mean of its divisors is an integer number (12893811).

Almost surely, 2^25787621 is an apocalyptic number.

It is an amenable number.

25787621 is a deficient number, since it is larger than the sum of its proper divisors (1).

25787621 is an equidigital number, since it uses as much as digits as its factorization.

25787621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040, while the sum is 38.

The square root of 25787621 is about 5078.1513368548. The cubic root of 25787621 is about 295.4407698106.

It can be divided in two parts, 257 and 87621, that added together give a palindrome (87878).

The spelling of 25787621 in words is "twenty-five million, seven hundred eighty-seven thousand, six hundred twenty-one".