21420323304 has 16 divisors (see below), whose sum is σ = 53550808320. Its totient is φ = 7140107760.

The previous prime is 21420323297. The next prime is 21420323311. The reversal of 21420323304 is 40332302412.

It is an interprime number because it is at equal distance from previous prime (21420323297) and next prime (21420323311).

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 892513471 = 21420323304 / (2 + 1 + 4 + 2 + 0 + 3 + 2 + 3 + 3 + 0 + 4).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 446256712 + ... + 446256759.

It is an arithmetic number, because the mean of its divisors is an integer number (3346925520).

Almost surely, 2^21420323304 is an apocalyptic number.

21420323304 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21420323304 is an abundant number, since it is smaller than the sum of its proper divisors (32130485016).

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

21420323304 is a wasteful number, since it uses less digits than its factorization.

21420323304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 892513480 (or 892513476 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 24.

Adding to 21420323304 its reverse (40332302412), we get a palindrome (61752625716).

The spelling of 21420323304 in words is "twenty-one billion, four hundred twenty million, three hundred twenty-three thousand, three hundred four".