21211222194 has 64 divisors (see below), whose sum is σ = 49454453760. Its totient is φ = 6730128000.

The previous prime is 21211222189. The next prime is 21211222217. The reversal of 21211222194 is 49122211212.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1747 + ... + 205974.

It is an arithmetic number, because the mean of its divisors is an integer number (772725840).

Almost surely, 2^21211222194 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21211222194, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24727226880).

21211222194 is an abundant number, since it is smaller than the sum of its proper divisors (28243231566).

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

21211222194 is a wasteful number, since it uses less digits than its factorization.

21211222194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207824 (or 207818 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The spelling of 21211222194 in words is "twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, one hundred ninety-four".