20870780 has 24 divisors (see below), whose sum is σ = 50090208. Its totient is φ = 7155648.

The previous prime is 20870779. The next prime is 20870783. The reversal of 20870780 is 8707802.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20870783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74399 + ... + 74678.

It is an arithmetic number, because the mean of its divisors is an integer number (2087092).

Almost surely, 2^20870780 is an apocalyptic number.

20870780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20870780 is an abundant number, since it is smaller than the sum of its proper divisors (29219428).

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

20870780 is a wasteful number, since it uses less digits than its factorization.

20870780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149093 (or 149091 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 32.

The square root of 20870780 is about 4568.4548810293. The cubic root of 20870780 is about 275.3253669555.

The spelling of 20870780 in words is "twenty million, eight hundred seventy thousand, seven hundred eighty".