21399160 has 32 divisors (see below), whose sum is σ = 48697200. Its totient is φ = 8462080.

The previous prime is 21399151. The next prime is 21399167. The reversal of 21399160 is 6199312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21399167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 555 + ... + 6565.

Almost surely, 2^21399160 is an apocalyptic number.

21399160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21399160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24348600).

21399160 is an abundant number, since it is smaller than the sum of its proper divisors (27298040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21399160 is a wasteful number, since it uses less digits than its factorization.

21399160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6111 (or 6107 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 21399160 is about 4625.9226106799. The cubic root of 21399160 is about 277.6294772243.

The spelling of 21399160 in words is "twenty-one million, three hundred ninety-nine thousand, one hundred sixty".