21402401300021 has 16 divisors (see below), whose sum is σ = 24542315635968. Its totient is φ = 18283112246400.

The previous prime is 21402401300003. The next prime is 21402401300029. The reversal of 21402401300021 is 12000310420412.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21402401300021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21402401299966 and 21402401300002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21402401300029) 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, 13442411 + ... + 14950023.

It is an arithmetic number, because the mean of its divisors is an integer number (1533894727248).

Almost surely, 2^{21402401300021} is an apocalyptic number.

It is an amenable number.

21402401300021 is a deficient number, since it is larger than the sum of its proper divisors (3139914335947).

21402401300021 is a wasteful number, since it uses less digits than its factorization.

21402401300021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1514452.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21402401300021 its reverse (12000310420412), we get a palindrome (33402711720433).

The spelling of 21402401300021 in words is "twenty-one trillion, four hundred two billion, four hundred one million, three hundred thousand, twenty-one".