21014432420 has 24 divisors (see below), whose sum is σ = 44145662904. Its totient is φ = 8402848256.

The previous prime is 21014432419. The next prime is 21014432441. The reversal of 21014432420 is 2423441012.

It can be written as a sum of positive squares in 4 ways, for example, as 4228120576 + 16786311844 = 65024^2 + 129562^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123407 + ... + 239286.

It is an arithmetic number, because the mean of its divisors is an integer number (1839402621).

Almost surely, 2^21014432420 is an apocalyptic number.

21014432420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21014432420 is an abundant number, since it is smaller than the sum of its proper divisors (23131230484).

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

21014432420 is a wasteful number, since it uses less digits than its factorization.

21014432420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365599 (or 365597 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21014432420 its reverse (2423441012), we get a palindrome (23437873432).

The spelling of 21014432420 in words is "twenty-one billion, fourteen million, four hundred thirty-two thousand, four hundred twenty".