21199707672 has 384 divisors, whose sum is σ = 66916523520. Its totient is φ = 5515776000.

The previous prime is 21199707667. The next prime is 21199707677. The reversal of 21199707672 is 27670799112.

It is an interprime number because it is at equal distance from previous prime (21199707667) and next prime (21199707677).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21199707677) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 87965472 + ... + 87965712.

It is an arithmetic number, because the mean of its divisors is an integer number (174261780).

Almost surely, 2^21199707672 is an apocalyptic number.

21199707672 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 21199707672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33458261760).

21199707672 is an abundant number, since it is smaller than the sum of its proper divisors (45716815848).

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

21199707672 is a wasteful number, since it uses less digits than its factorization.

21199707672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 666792, while the sum is 51.

The spelling of 21199707672 in words is "twenty-one billion, one hundred ninety-nine million, seven hundred seven thousand, six hundred seventy-two".