21150402320 has 80 divisors (see below), whose sum is σ = 50275710720. Its totient is φ = 8271132672.

The previous prime is 21150402313. The next prime is 21150402323. The reversal of 21150402320 is 2320405112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×21150402320² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21150402292 and 21150402301.

It is not an unprimeable number, because it can be changed into a prime (21150402323) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4219976 + ... + 4224984.

It is an arithmetic number, because the mean of its divisors is an integer number (628446384).

Almost surely, 2^21150402320 is an apocalyptic number.

21150402320 is a gapful number since it is divisible by the number (20) 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 21150402320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25137855360).

21150402320 is an abundant number, since it is smaller than the sum of its proper divisors (29125308400).

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

21150402320 is a wasteful number, since it uses less digits than its factorization.

21150402320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6192 (or 6186 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21150402320 its reverse (2320405112), we get a palindrome (23470807432).

The spelling of 21150402320 in words is "twenty-one billion, one hundred fifty million, four hundred two thousand, three hundred twenty".