21274351572 has 24 divisors (see below), whose sum is σ = 49647318336. Its totient is φ = 7090427008.

The previous prime is 21274351559. The next prime is 21274351577. The reversal of 21274351572 is 27515347212.

It is a self number, because there is not a number n which added to its sum of digits gives 21274351572.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21274351577) 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, 38853 + ... + 209900.

It is an arithmetic number, because the mean of its divisors is an integer number (2068638264).

Almost surely, 2^21274351572 is an apocalyptic number.

It is an amenable number.

21274351572 is an abundant number, since it is smaller than the sum of its proper divisors (28372966764).

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

21274351572 is a wasteful number, since it uses less digits than its factorization.

21274351572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255887 (or 255885 counting only the distinct ones).

The product of its digits is 117600, while the sum is 39.

Adding to 21274351572 its reverse (27515347212), we get a palindrome (48789698784).

The spelling of 21274351572 in words is "twenty-one billion, two hundred seventy-four million, three hundred fifty-one thousand, five hundred seventy-two".