21756900587 has 2 divisors, whose sum is σ = 21756900588. Its totient is φ = 21756900586.

The previous prime is 21756900569. The next prime is 21756900601. The reversal of 21756900587 is 78500965712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21756900587 - 2⁶ = 21756900523 is a prime.

It is not a weakly prime, because it can be changed into another prime (21756900527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10878450293 + 10878450294.

It is an arithmetic number, because the mean of its divisors is an integer number (10878450294).

Almost surely, 2^21756900587 is an apocalyptic number.

21756900587 is a deficient number, since it is larger than the sum of its proper divisors (1).

21756900587 is an equidigital number, since it uses as much as digits as its factorization.

21756900587 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1058400, while the sum is 50.

The spelling of 21756900587 in words is "twenty-one billion, seven hundred fifty-six million, nine hundred thousand, five hundred eighty-seven".