20776631 has 2 divisors, whose sum is σ = 20776632. Its totient is φ = 20776630.

The previous prime is 20776621. The next prime is 20776663. The reversal of 20776631 is 13667702.

It is an a-pointer prime, because the next prime (20776663) can be obtained adding 20776631 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20776631 is a prime.

It is a super-2 number, since 2×20776631² = 863336791420322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20776621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10388315 + 10388316.

It is an arithmetic number, because the mean of its divisors is an integer number (10388316).

Almost surely, 2^20776631 is an apocalyptic number.

20776631 is a deficient number, since it is larger than the sum of its proper divisors (1).

20776631 is an equidigital number, since it uses as much as digits as its factorization.

20776631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10584, while the sum is 32.

The square root of 20776631 is about 4558.1389842786. The cubic root of 20776631 is about 274.9107412797.

The spelling of 20776631 in words is "twenty million, seven hundred seventy-six thousand, six hundred thirty-one".