21400200243021 has 64 divisors (see below), whose sum is σ = 31662078543360. Its totient is φ = 12832653532160.

The previous prime is 21400200243013. The next prime is 21400200243029. The reversal of 21400200243021 is 12034200200412.

It is an interprime number because it is at equal distance from previous prime (21400200243013) and next prime (21400200243029).

It is not a de Polignac number, because 21400200243021 - 2³ = 21400200243013 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21400200243029) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 400328731 + ... + 400382183.

It is an arithmetic number, because the mean of its divisors is an integer number (494719977240).

Almost surely, 2^{21400200243021} is an apocalyptic number.

It is an amenable number.

21400200243021 is a deficient number, since it is larger than the sum of its proper divisors (10261878300339).

21400200243021 is a wasteful number, since it uses less digits than its factorization.

21400200243021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54711 (or 54677 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21400200243021 its reverse (12034200200412), we get a palindrome (33434400443433).

The spelling of 21400200243021 in words is "twenty-one trillion, four hundred billion, two hundred million, two hundred forty-three thousand, twenty-one".