21690686376 has 96 divisors (see below), whose sum is σ = 62514504000. Its totient is φ = 6770649600.

The previous prime is 21690686363. The next prime is 21690686389. The reversal of 21690686376 is 67368609612.

It is an interprime number because it is at equal distance from previous prime (21690686363) and next prime (21690686389).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 199051 + ... + 288101.

It is an arithmetic number, because the mean of its divisors is an integer number (651192750).

Almost surely, 2^21690686376 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 21690686376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31257252000).

21690686376 is an abundant number, since it is smaller than the sum of its proper divisors (40823817624).

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

21690686376 is a wasteful number, since it uses less digits than its factorization.

21690686376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89279 (or 89272 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 54.

The spelling of 21690686376 in words is "twenty-one billion, six hundred ninety million, six hundred eighty-six thousand, three hundred seventy-six".