21210253311 has 16 divisors (see below), whose sum is σ = 30554969984. Its totient is φ = 13009940064.

The previous prime is 21210253277. The next prime is 21210253319. The reversal of 21210253311 is 11335201212.

It is a de Polignac number, because none of the positive numbers 2^k-21210253311 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 (21210253319) 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, 873781 + ... + 897726.

It is an arithmetic number, because the mean of its divisors is an integer number (1909685624).

Almost surely, 2^21210253311 is an apocalyptic number.

21210253311 is a deficient number, since it is larger than the sum of its proper divisors (9344716673).

21210253311 is a wasteful number, since it uses less digits than its factorization.

21210253311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1771830.

The product of its (nonzero) digits is 360, while the sum is 21.

Adding to 21210253311 its reverse (11335201212), we get a palindrome (32545454523).

The spelling of 21210253311 in words is "twenty-one billion, two hundred ten million, two hundred fifty-three thousand, three hundred eleven".