21232404402 has 64 divisors (see below), whose sum is σ = 47899289088. Its totient is φ = 6218384000.

The previous prime is 21232404397. The next prime is 21232404451. The reversal of 21232404402 is 20440423212.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 252877 + ... + 326207.

It is an arithmetic number, because the mean of its divisors is an integer number (748426392).

Almost surely, 2^21232404402 is an apocalyptic number.

21232404402 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21232404402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23949644544).

21232404402 is an abundant number, since it is smaller than the sum of its proper divisors (26666884686).

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

21232404402 is a wasteful number, since it uses less digits than its factorization.

21232404402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73495.

The product of its (nonzero) digits is 3072, while the sum is 24.

Adding to 21232404402 its reverse (20440423212), we get a palindrome (41672827614).

The spelling of 21232404402 in words is "twenty-one billion, two hundred thirty-two million, four hundred four thousand, four hundred two".