21200421351 has 16 divisors (see below), whose sum is σ = 28737375968. Its totient is φ = 13898649600.

The previous prime is 21200421349. The next prime is 21200421401. The reversal of 21200421351 is 15312400212.

It is not a de Polignac number, because 21200421351 - 2¹ = 21200421349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200441351) 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, 955455 + ... + 977391.

It is an arithmetic number, because the mean of its divisors is an integer number (1796085998).

Almost surely, 2^21200421351 is an apocalyptic number.

21200421351 is a deficient number, since it is larger than the sum of its proper divisors (7536954617).

21200421351 is a wasteful number, since it uses less digits than its factorization.

21200421351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27282.

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 21200421351 its reverse (15312400212), we get a palindrome (36512821563).

The spelling of 21200421351 in words is "twenty-one billion, two hundred million, four hundred twenty-one thousand, three hundred fifty-one".