21782610872 has 32 divisors (see below), whose sum is σ = 45642063600. Its totient is φ = 9659692800.

The previous prime is 21782610869. The next prime is 21782610887. The reversal of 21782610872 is 27801628712.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3015047 + ... + 3022262.

Almost surely, 2^21782610872 is an apocalyptic number.

21782610872 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21782610872 is an abundant number, since it is smaller than the sum of its proper divisors (23859452728).

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

21782610872 is a wasteful number, since it uses less digits than its factorization.

21782610872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6037367 (or 6037363 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 44.

The spelling of 21782610872 in words is "twenty-one billion, seven hundred eighty-two million, six hundred ten thousand, eight hundred seventy-two".