21211201118 has 4 divisors (see below), whose sum is σ = 31816801680. Its totient is φ = 10605600558.

The previous prime is 21211201111. The next prime is 21211201139. The reversal of 21211201118 is 81110211212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21211201118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211201111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302800278 + ... + 5302800281.

It is an arithmetic number, because the mean of its divisors is an integer number (7954200420).

Almost surely, 2^21211201118 is an apocalyptic number.

21211201118 is a deficient number, since it is larger than the sum of its proper divisors (10605600562).

21211201118 is a wasteful number, since it uses less digits than its factorization.

21211201118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10605600561.

The product of its (nonzero) digits is 64, while the sum is 20.

The spelling of 21211201118 in words is "twenty-one billion, two hundred eleven million, two hundred one thousand, one hundred eighteen".