21011311323420 has 72 divisors (see below), whose sum is σ = 64666217682192. Its totient is φ = 5093651228160.

The previous prime is 21011311323419. The next prime is 21011311323461. The reversal of 21011311323420 is 2432311311012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1447052749 + ... + 1447067268.

Almost surely, 2^{21011311323420} is an apocalyptic number.

21011311323420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011311323420 is an abundant number, since it is smaller than the sum of its proper divisors (43654906358772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21011311323420 is a wasteful number, since it uses less digits than its factorization.

21011311323420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2894120051 (or 2894120038 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21011311323420 its reverse (2432311311012), we get a palindrome (23443622634432).

The spelling of 21011311323420 in words is "twenty-one trillion, eleven billion, three hundred eleven million, three hundred twenty-three thousand, four hundred twenty".