21710120 has 32 divisors (see below), whose sum is σ = 50171400. Its totient is φ = 8448768.

The previous prime is 21710113. The next prime is 21710123. The reversal of 21710120 is 2101712.

It can be written as a sum of positive squares in 4 ways, for example, as 21141604 + 568516 = 4598^2 + 754^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21710095 and 21710104.

It is not an unprimeable number, because it can be changed into a prime (21710123) 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, 5855 + ... + 8814.

Almost surely, 2^21710120 is an apocalyptic number.

21710120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21710120 is an abundant number, since it is smaller than the sum of its proper divisors (28461280).

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

21710120 is a wasteful number, since it uses less digits than its factorization.

21710120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14717 (or 14713 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 14.

The square root of 21710120 is about 4659.4119800679. The cubic root of 21710120 is about 278.9677981702.

Adding to 21710120 its reverse (2101712), we get a palindrome (23811832).

The spelling of 21710120 in words is "twenty-one million, seven hundred ten thousand, one hundred twenty".