20867780 has 24 divisors (see below), whose sum is σ = 44425752. Its totient is φ = 8232192.

The previous prime is 20867773. The next prime is 20867809. The reversal of 20867780 is 8776802.

It can be written as a sum of positive squares in 4 ways, for example, as 1156 + 20866624 = 34^2 + 4568^2 .

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5687 + ... + 8606.

It is an arithmetic number, because the mean of its divisors is an integer number (1851073).

Almost surely, 2^20867780 is an apocalyptic number.

20867780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20867780 is an abundant number, since it is smaller than the sum of its proper divisors (23557972).

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

20867780 is a wasteful number, since it uses less digits than its factorization.

20867780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14375 (or 14373 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 38.

The square root of 20867780 is about 4568.1265306469. The cubic root of 20867780 is about 275.3121744175.

The spelling of 20867780 in words is "twenty million, eight hundred sixty-seven thousand, seven hundred eighty".