21014420831 has 16 divisors (see below), whose sum is σ = 22226400000. Its totient is φ = 19813280256.

The previous prime is 21014420827. The next prime is 21014420881. The reversal of 21014420831 is 13802441012.

It is not a de Polignac number, because 21014420831 - 2² = 21014420827 is a prime.

It is a super-2 number, since 2×21014420831² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21014420831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21014420881) 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, 3571550 + ... + 3577428.

It is an arithmetic number, because the mean of its divisors is an integer number (1389150000).

Almost surely, 2^21014420831 is an apocalyptic number.

21014420831 is a deficient number, since it is larger than the sum of its proper divisors (1211979169).

21014420831 is a wasteful number, since it uses less digits than its factorization.

21014420831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6766.

The product of its (nonzero) digits is 1536, while the sum is 26.

Adding to 21014420831 its reverse (13802441012), we get a palindrome (34816861843).

The spelling of 21014420831 in words is "twenty-one billion, fourteen million, four hundred twenty thousand, eight hundred thirty-one".