636131479 has 2 divisors, whose sum is σ = 636131480. Its totient is φ = 636131478.

The previous prime is 636131477. The next prime is 636131519. The reversal of 636131479 is 974131636.

It is an a-pointer prime, because the next prime (636131519) can be obtained adding 636131479 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 636131479 - 2¹ = 636131477 is a prime.

Together with 636131477, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (636131471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318065739 + 318065740.

It is an arithmetic number, because the mean of its divisors is an integer number (318065740).

Almost surely, 2^636131479 is an apocalyptic number.

636131479 is a deficient number, since it is larger than the sum of its proper divisors (1).

636131479 is an equidigital number, since it uses as much as digits as its factorization.

636131479 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 40.

The square root of 636131479 is about 25221.6470318653. The cubic root of 636131479 is about 860.0340165921.

The spelling of 636131479 in words is "six hundred thirty-six million, one hundred thirty-one thousand, four hundred seventy-nine".