21951360 has 192 divisors, whose sum is σ = 78605280. Its totient is φ = 5640192.

The previous prime is 21951353. The next prime is 21951367. The reversal of 21951360 is 6315912.

It is an interprime number because it is at equal distance from previous prime (21951353) and next prime (21951367).

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21951367) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 213069 + ... + 213171.

Almost surely, 2^21951360 is an apocalyptic number.

21951360 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 21951360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39302640).

21951360 is an abundant number, since it is smaller than the sum of its proper divisors (56653920).

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

21951360 is a wasteful number, since it uses less digits than its factorization.

21951360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 21951360 is about 4685.2278493153. The cubic root of 21951360 is about 279.9972788851.

The spelling of 21951360 in words is "twenty-one million, nine hundred fifty-one thousand, three hundred sixty".