21385674432 has 140 divisors (see below), whose sum is σ = 63977123760. Its totient is φ = 7062971904.

The previous prime is 21385674419. The next prime is 21385674439. The reversal of 21385674432 is 23447658312.

21385674432 is a `hidden beast` number, since 2 + 13 + 8 + 567 + 44 + 32 = 666.

It is a super-2 number, since 2×21385674432² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21385674439) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 546133 + ... + 583979.

Almost surely, 2^21385674432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21385674432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31988561880).

21385674432 is an abundant number, since it is smaller than the sum of its proper divisors (42591449328).

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

21385674432 is a wasteful number, since it uses less digits than its factorization.

21385674432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37980 (or 37961 counting only the distinct ones).

The product of its digits is 967680, while the sum is 45.

The spelling of 21385674432 in words is "twenty-one billion, three hundred eighty-five million, six hundred seventy-four thousand, four hundred thirty-two".