20878722 has 30 divisors (see below), whose sum is σ = 46914483. Its totient is φ = 6940188.

The previous prime is 20878721. The next prime is 20878723. The reversal of 20878722 is 22787802.

It is an interprime number because it is at equal distance from previous prime (20878721) and next prime (20878723).

It can be written as a sum of positive squares in only one way, i.e., 10439361 + 10439361 = 3231^2 + 3231^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3231.

It is not an unprimeable number, because it can be changed into a prime (20878721) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 57979 + ... + 58337.

Almost surely, 2^20878722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20878722

20878722 is an abundant number, since it is smaller than the sum of its proper divisors (26035761).

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

20878722 is an frugal number, since it uses more digits than its factorization.

20878722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 364 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 20878722 is about 4569.3240200275. The cubic root of 20878722 is about 275.3602858990.

Multiplying 20878722 by its product of nonzero digits (25088), we get a square (523805377536 = 723744²).

The spelling of 20878722 in words is "twenty million, eight hundred seventy-eight thousand, seven hundred twenty-two".