21205440274 has 8 divisors (see below), whose sum is σ = 31809570048. Its totient is φ = 10602250260.

The previous prime is 21205440271. The next prime is 21205440293. The reversal of 21205440274 is 47204450212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21205440271) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 175522 + ... + 270589.

It is an arithmetic number, because the mean of its divisors is an integer number (3976196256).

Almost surely, 2^21205440274 is an apocalyptic number.

21205440274 is a deficient number, since it is larger than the sum of its proper divisors (10604129774).

21205440274 is a wasteful number, since it uses less digits than its factorization.

21205440274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469880.

The product of its (nonzero) digits is 17920, while the sum is 31.

Adding to 21205440274 its reverse (47204450212), we get a palindrome (68409890486).

The spelling of 21205440274 in words is "twenty-one billion, two hundred five million, four hundred forty thousand, two hundred seventy-four".