21436627968 has 528 divisors, whose sum is σ = 75917563904. Its totient is φ = 5912248320.

The previous prime is 21436627967. The next prime is 21436627973. The reversal of 21436627968 is 86972663412.

21436627968 is a `hidden beast` number, since 2 + 1 + 4 + 3 + 6 + 627 + 9 + 6 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436627967) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 53996346 + ... + 53996742.

Almost surely, 2^21436627968 is an apocalyptic number.

21436627968 is a gapful number since it is divisible by the number (28) 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 21436627968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37958781952).

21436627968 is an abundant number, since it is smaller than the sum of its proper divisors (54480935936).

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

21436627968 is an equidigital number, since it uses as much as digits as its factorization.

21436627968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470 (or 440 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 54.

The spelling of 21436627968 in words is "twenty-one billion, four hundred thirty-six million, six hundred twenty-seven thousand, nine hundred sixty-eight".