26401631 has 4 divisors (see below), whose sum is σ = 27549552. Its totient is φ = 25253712.

The previous prime is 26401619. The next prime is 26401643. The reversal of 26401631 is 13610462.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (26401619) and next prime (26401643).

It is a cyclic number.

It is not a de Polignac number, because 26401631 - 2⁶ = 26401567 is a prime.

It is a super-2 number, since 2×26401631² = 1394092238920322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 1147897 = 26401631 / (2 + 6 + 4 + 0 + 1 + 6 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 26401597 and 26401606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26401601) 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, 573926 + ... + 573971.

It is an arithmetic number, because the mean of its divisors is an integer number (6887388).

Almost surely, 2^26401631 is an apocalyptic number.

26401631 is a deficient number, since it is larger than the sum of its proper divisors (1147921).

26401631 is a wasteful number, since it uses less digits than its factorization.

26401631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147920.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 26401631 is about 5138.2517454870. The cubic root of 26401631 is about 297.7672423884.

The spelling of 26401631 in words is "twenty-six million, four hundred one thousand, six hundred thirty-one".