21090095 has 16 divisors (see below), whose sum is σ = 28691040. Its totient is φ = 14753664.

The previous prime is 21090073. The next prime is 21090101. The reversal of 21090095 is 59009012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21090095 - 2⁸ = 21089839 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7304 + ... + 9773.

It is an arithmetic number, because the mean of its divisors is an integer number (1793190).

Almost surely, 2^21090095 is an apocalyptic number.

21090095 is a deficient number, since it is larger than the sum of its proper divisors (7600945).

21090095 is a wasteful number, since it uses less digits than its factorization.

21090095 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17114.

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 21090095 is about 4592.3953444798. The cubic root of 21090095 is about 276.2864027975.

The spelling of 21090095 in words is "twenty-one million, ninety thousand, ninety-five".