20749872 has 80 divisors (see below), whose sum is σ = 62995968. Its totient is φ = 5802240.

The previous prime is 20749837. The next prime is 20749879. The reversal of 20749872 is 27894702.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 20749872.

It is not an unprimeable number, because it can be changed into a prime (20749879) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5353 + ... + 8375.

Almost surely, 2^20749872 is an apocalyptic number.

20749872 is a gapful number since it is divisible by the number (22) 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 20749872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31497984).

20749872 is an abundant number, since it is smaller than the sum of its proper divisors (42246096).

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

20749872 is a wasteful number, since it uses less digits than its factorization.

20749872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3058 (or 3052 counting only the distinct ones).

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

The square root of 20749872 is about 4555.2027397252. The cubic root of 20749872 is about 274.7926679669.

The spelling of 20749872 in words is "twenty million, seven hundred forty-nine thousand, eight hundred seventy-two".