20877440 has 32 divisors (see below), whose sum is σ = 49911660. Its totient is φ = 8350720.

The previous prime is 20877431. The next prime is 20877443. The reversal of 20877440 is 4477802.

It can be written as a sum of positive squares in 2 ways, for example, as 20866624 + 10816 = 4568^2 + 104^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 20877397 and 20877406.

It is not an unprimeable number, because it can be changed into a prime (20877443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15671 + ... + 16950.

Almost surely, 2^20877440 is an apocalyptic number.

20877440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20877440 is an abundant number, since it is smaller than the sum of its proper divisors (29034220).

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

20877440 is an equidigital number, since it uses as much as digits as its factorization.

20877440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32640 (or 32628 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 32.

The square root of 20877440 is about 4569.1837345417. The cubic root of 20877440 is about 275.3546498722.

The spelling of 20877440 in words is "twenty million, eight hundred seventy-seven thousand, four hundred forty".