21508089106 has 96 divisors (see below), whose sum is σ = 39796323840. Its totient is φ = 8689131360.

The previous prime is 21508089101. The next prime is 21508089133. The reversal of 21508089106 is 60198080512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21508089101) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 154734385 + ... + 154734523.

It is an arithmetic number, because the mean of its divisors is an integer number (414545040).

Almost surely, 2^21508089106 is an apocalyptic number.

21508089106 is a deficient number, since it is larger than the sum of its proper divisors (18288234734).

21508089106 is an equidigital number, since it uses as much as digits as its factorization.

21508089106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 301 (or 232 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 40.

The spelling of 21508089106 in words is "twenty-one billion, five hundred eight million, eighty-nine thousand, one hundred six".