21700885 has 8 divisors (see below), whose sum is σ = 26083800. Its totient is φ = 17332224.

The previous prime is 21700883. The next prime is 21700901. The reversal of 21700885 is 58800712.

It can be written as a sum of positive squares in 4 ways, for example, as 5716881 + 15984004 = 2391^2 + 3998^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21700885 - 2¹ = 21700883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21700883) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 141 + ... + 6589.

It is an arithmetic number, because the mean of its divisors is an integer number (3260475).

Almost surely, 2^21700885 is an apocalyptic number.

It is an amenable number.

21700885 is a deficient number, since it is larger than the sum of its proper divisors (4382915).

21700885 is an equidigital number, since it uses as much as digits as its factorization.

21700885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7127.

The product of its (nonzero) digits is 4480, while the sum is 31.

The square root of 21700885 is about 4658.4208697798. The cubic root of 21700885 is about 278.9282370040.

The spelling of 21700885 in words is "twenty-one million, seven hundred thousand, eight hundred eighty-five".