20861378620 has 48 divisors (see below), whose sum is σ = 45496902528. Its totient is φ = 8028820800.

The previous prime is 20861378597. The next prime is 20861378641. The reversal of 20861378620 is 2687316802.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 123406 + ... + 238645.

It is an arithmetic number, because the mean of its divisors is an integer number (947852136).

Almost surely, 2^20861378620 is an apocalyptic number.

20861378620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20861378620 is an abundant number, since it is smaller than the sum of its proper divisors (24635523908).

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

20861378620 is a wasteful number, since it uses less digits than its factorization.

20861378620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362170 (or 362168 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 20861378620 in words is "twenty billion, eight hundred sixty-one million, three hundred seventy-eight thousand, six hundred twenty".