21086836452 has 72 divisors (see below), whose sum is σ = 58398369120. Its totient is φ = 6362497920.

The previous prime is 21086836451. The next prime is 21086836453. The reversal of 21086836452 is 25463868012.

21086836452 is a `hidden beast` number, since 2 + 108 + 68 + 36 + 452 = 666.

It is an interprime number because it is at equal distance from previous prime (21086836451) and next prime (21086836453).

It is a junction number, because it is equal to n+sod(n) for n = 21086836398 and 21086836407.

It is not an unprimeable number, because it can be changed into a prime (21086836451) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22002 + ... + 206537.

It is an arithmetic number, because the mean of its divisors is an integer number (811088460).

Almost surely, 2^21086836452 is an apocalyptic number.

21086836452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21086836452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29199184560).

21086836452 is an abundant number, since it is smaller than the sum of its proper divisors (37311532668).

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

21086836452 is a wasteful number, since it uses less digits than its factorization.

21086836452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228793 (or 228788 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 21086836452 in words is "twenty-one billion, eighty-six million, eight hundred thirty-six thousand, four hundred fifty-two".