21970260 has 144 divisors (see below), whose sum is σ = 73841040. Its totient is φ = 5253120.

The previous prime is 21970229. The next prime is 21970271. The reversal of 21970260 is 6207912.

It can be written as a sum of positive squares in 8 ways, for example, as 1774224 + 20196036 = 1332^2 + 4494^2 .

It is a zygodrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 95826 + ... + 96054.

It is an arithmetic number, because the mean of its divisors is an integer number (512785).

Almost surely, 2^21970260 is an apocalyptic number.

21970260 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 21970260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36920520).

21970260 is an abundant number, since it is smaller than the sum of its proper divisors (51870780).

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

21970260 is a wasteful number, since it uses less digits than its factorization.

21970260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298 (or 293 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21970260 is about 4687.2443930309. The cubic root of 21970260 is about 280.0776145381.

The spelling of 21970260 in words is "twenty-one million, nine hundred seventy thousand, two hundred sixty".