20977824 has 192 divisors, whose sum is σ = 69672960. Its totient is φ = 5391360.

The previous prime is 20977819. The next prime is 20977841. The reversal of 20977824 is 42877902.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 395782 + ... + 395834.

It is an arithmetic number, because the mean of its divisors is an integer number (362880).

Almost surely, 2^20977824 is an apocalyptic number.

20977824 is a gapful number since it is divisible by the number (24) 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 20977824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34836480).

20977824 is an abundant number, since it is smaller than the sum of its proper divisors (48695136).

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

20977824 is a wasteful number, since it uses less digits than its factorization.

20977824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 20977824 is about 4580.1554558770. The cubic root of 20977824 is about 275.7952693029.

The spelling of 20977824 in words is "twenty million, nine hundred seventy-seven thousand, eight hundred twenty-four".