20997600 has 144 divisors (see below), whose sum is σ = 73714032. Its totient is φ = 5160960.

The previous prime is 20997583. The next prime is 20997619. The reversal of 20997600 is 679902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30864 + ... + 31536.

It is an arithmetic number, because the mean of its divisors is an integer number (511903).

Almost surely, 2^20997600 is an apocalyptic number.

20997600 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 20997600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36857016).

20997600 is an abundant number, since it is smaller than the sum of its proper divisors (52716432).

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

20997600 is a wasteful number, since it uses less digits than its factorization.

20997600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709 (or 696 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 33.

The square root of 20997600 is about 4582.3138260054. The cubic root of 20997600 is about 275.8819070504.

The spelling of 20997600 in words is "twenty million, nine hundred ninety-seven thousand, six hundred".