21320160 has 48 divisors (see below), whose sum is σ = 67160016. Its totient is φ = 5685248.

The previous prime is 21320107. The next prime is 21320183. The reversal of 21320160 is 6102312.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21729 + ... + 22688.

It is an arithmetic number, because the mean of its divisors is an integer number (1399167).

Almost surely, 2^21320160 is an apocalyptic number.

21320160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21320160 is an abundant number, since it is smaller than the sum of its proper divisors (45839856).

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

21320160 is a wasteful number, since it uses less digits than its factorization.

21320160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44435 (or 44427 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 21320160 is about 4617.3758781368. The cubic root of 21320160 is about 277.2874112409.

Adding to 21320160 its reverse (6102312), we get a palindrome (27422472).

The spelling of 21320160 in words is "twenty-one million, three hundred twenty thousand, one hundred sixty".