26221631 has 2 divisors, whose sum is σ = 26221632. Its totient is φ = 26221630.

The previous prime is 26221627. The next prime is 26221639. The reversal of 26221631 is 13612262.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 26221631 - 2² = 26221627 is a prime.

It is a super-2 number, since 2×26221631² = 1375147864600322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 26221597 and 26221606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26221639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13110815 + 13110816.

It is an arithmetic number, because the mean of its divisors is an integer number (13110816).

Almost surely, 2^26221631 is an apocalyptic number.

26221631 is a deficient number, since it is larger than the sum of its proper divisors (1).

26221631 is an equidigital number, since it uses as much as digits as its factorization.

26221631 is an evil number, because the sum of its binary digits is even.

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

The square root of 26221631 is about 5120.7061036541. The cubic root of 26221631 is about 297.0889967471.

Adding to 26221631 its reverse (13612262), we get a palindrome (39833893).

The spelling of 26221631 in words is "twenty-six million, two hundred twenty-one thousand, six hundred thirty-one".