21629198194 has 4 divisors (see below), whose sum is σ = 32443797294. Its totient is φ = 10814599096.

The previous prime is 21629198119. The next prime is 21629198197. The reversal of 21629198194 is 49189192612.

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

It can be written as a sum of positive squares in only one way, i.e., 20110926969 + 1518271225 = 141813^2 + 38965^2 .

It is not an unprimeable number, because it can be changed into a prime (21629198197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5407299547 + ... + 5407299550.

Almost surely, 2^21629198194 is an apocalyptic number.

21629198194 is a deficient number, since it is larger than the sum of its proper divisors (10814599100).

21629198194 is a wasteful number, since it uses less digits than its factorization.

21629198194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10814599099.

The product of its digits is 559872, while the sum is 52.

The spelling of 21629198194 in words is "twenty-one billion, six hundred twenty-nine million, one hundred ninety-eight thousand, one hundred ninety-four".