21220220174 has 16 divisors (see below), whose sum is σ = 31989952512. Its totient is φ = 10556953368.

The previous prime is 21220220173. The next prime is 21220220237. The reversal of 21220220174 is 47102202212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220220173) 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, 908567 + ... + 931629.

It is an arithmetic number, because the mean of its divisors is an integer number (1999372032).

Almost surely, 2^21220220174 is an apocalyptic number.

21220220174 is a deficient number, since it is larger than the sum of its proper divisors (10769732338).

21220220174 is a wasteful number, since it uses less digits than its factorization.

21220220174 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25351.

The product of its (nonzero) digits is 896, while the sum is 23.

Adding to 21220220174 its reverse (47102202212), we get a palindrome (68322422386).

The spelling of 21220220174 in words is "twenty-one billion, two hundred twenty million, two hundred twenty thousand, one hundred seventy-four".