21677469780 has 48 divisors (see below), whose sum is σ = 61133607360. Its totient is φ = 5739068928.

The previous prime is 21677469733. The next prime is 21677469787. The reversal of 21677469780 is 8796477612.

It is a self number, because there is not a number n which added to its sum of digits gives 21677469780.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21677469787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1291269 + ... + 1307948.

It is an arithmetic number, because the mean of its divisors is an integer number (1273616820).

Almost surely, 2^21677469780 is an apocalyptic number.

21677469780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21677469780 is an abundant number, since it is smaller than the sum of its proper divisors (39456137580).

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

21677469780 is a wasteful number, since it uses less digits than its factorization.

21677469780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2599368 (or 2599366 counting only the distinct ones).

The product of its (nonzero) digits is 7112448, while the sum is 57.

The spelling of 21677469780 in words is "twenty-one billion, six hundred seventy-seven million, four hundred sixty-nine thousand, seven hundred eighty".