21002400401 has 8 divisors (see below), whose sum is σ = 21460564224. Its totient is φ = 20544707680.

The previous prime is 21002400373. The next prime is 21002400413. The reversal of 21002400401 is 10400420012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21002400401 - 2³⁰ = 19928658577 is a prime.

It is a super-2 number, since 2×21002400401² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21002402401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26885 + ... + 206706.

It is an arithmetic number, because the mean of its divisors is an integer number (2682570528).

Almost surely, 2^21002400401 is an apocalyptic number.

It is an amenable number.

21002400401 is a deficient number, since it is larger than the sum of its proper divisors (458163823).

21002400401 is a wasteful number, since it uses less digits than its factorization.

21002400401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235551.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21002400401 its reverse (10400420012), we get a palindrome (31402820413).

The spelling of 21002400401 in words is "twenty-one billion, two million, four hundred thousand, four hundred one".