21431304213044 has 24 divisors (see below), whose sum is σ = 40915415247168. Its totient is φ = 9741238295040.

The previous prime is 21431304213043. The next prime is 21431304213079. The reversal of 21431304213044 is 44031240313412.

It is a self number, because there is not a number n which added to its sum of digits gives 21431304213044.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21431304213041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4941464 + ... + 8202479.

It is an arithmetic number, because the mean of its divisors is an integer number (1704808968632).

Almost surely, 2^{21431304213044} is an apocalyptic number.

It is an amenable number.

21431304213044 is a deficient number, since it is larger than the sum of its proper divisors (19484111034124).

21431304213044 is a wasteful number, since it uses less digits than its factorization.

21431304213044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13181015 (or 13181013 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

Adding to 21431304213044 its reverse (44031240313412), we get a palindrome (65462544526456).

The spelling of 21431304213044 in words is "twenty-one trillion, four hundred thirty-one billion, three hundred four million, two hundred thirteen thousand, forty-four".