21087122 has 8 divisors (see below), whose sum is σ = 36149376. Its totient is φ = 9037332.

The previous prime is 21087061. The next prime is 21087133. The reversal of 21087122 is 22178012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 753098 + ... + 753125.

It is an arithmetic number, because the mean of its divisors is an integer number (4518672).

Almost surely, 2^21087122 is an apocalyptic number.

21087122 is a deficient number, since it is larger than the sum of its proper divisors (15062254).

21087122 is a wasteful number, since it uses less digits than its factorization.

21087122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1506232.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 21087122 is about 4592.0716457825. The cubic root of 21087122 is about 276.2734197981.

The spelling of 21087122 in words is "twenty-one million, eighty-seven thousand, one hundred twenty-two".