21512762827 has 2 divisors, whose sum is σ = 21512762828. Its totient is φ = 21512762826.

The previous prime is 21512762809. The next prime is 21512762849. The reversal of 21512762827 is 72826721512.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21512762827 is a prime.

It is not a weakly prime, because it can be changed into another prime (21512762807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10756381413 + 10756381414.

It is an arithmetic number, because the mean of its divisors is an integer number (10756381414).

Almost surely, 2^21512762827 is an apocalyptic number.

21512762827 is a deficient number, since it is larger than the sum of its proper divisors (1).

21512762827 is an equidigital number, since it uses as much as digits as its factorization.

21512762827 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 188160, while the sum is 43.

The spelling of 21512762827 in words is "twenty-one billion, five hundred twelve million, seven hundred sixty-two thousand, eight hundred twenty-seven".