21205474442 has 16 divisors (see below), whose sum is σ = 31908695040. Its totient is φ = 10569273792.

The previous prime is 21205474441. The next prime is 21205474471. The reversal of 21205474442 is 24447450212.

It is a super-2 number, since 2×21205474442² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21205474441) 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, 1624313 + ... + 1637315.

It is an arithmetic number, because the mean of its divisors is an integer number (1994293440).

Almost surely, 2^21205474442 is an apocalyptic number.

21205474442 is a deficient number, since it is larger than the sum of its proper divisors (10703220598).

21205474442 is a wasteful number, since it uses less digits than its factorization.

21205474442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15517.

The product of its (nonzero) digits is 71680, while the sum is 35.

The spelling of 21205474442 in words is "twenty-one billion, two hundred five million, four hundred seventy-four thousand, four hundred forty-two".