21970980 has 192 divisors, whose sum is σ = 74995200. Its totient is φ = 5322240.

The previous prime is 21970969. The next prime is 21970981. The reversal of 21970980 is 8907912.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21970981) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 360150 + ... + 360210.

It is an arithmetic number, because the mean of its divisors is an integer number (390600).

Almost surely, 2^21970980 is an apocalyptic number.

21970980 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 21970980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37497600).

21970980 is an abundant number, since it is smaller than the sum of its proper divisors (53024220).

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

21970980 is a wasteful number, since it uses less digits than its factorization.

21970980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 21970980 is about 4687.3211965898. The cubic root of 21970980 is about 280.0806740328.

The spelling of 21970980 in words is "twenty-one million, nine hundred seventy thousand, nine hundred eighty".