21030402194 has 8 divisors (see below), whose sum is σ = 33401227068. Its totient is φ = 9896659840.

The previous prime is 21030402193. The next prime is 21030402229. The reversal of 21030402194 is 49120403012.

It can be written as a sum of positive squares in 2 ways, for example, as 21006733969 + 23668225 = 144937^2 + 4865^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21030402191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309270587 + ... + 309270654.

Almost surely, 2^21030402194 is an apocalyptic number.

21030402194 is a deficient number, since it is larger than the sum of its proper divisors (12370824874).

21030402194 is a wasteful number, since it uses less digits than its factorization.

21030402194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618541260.

The product of its (nonzero) digits is 1728, while the sum is 26.

The spelling of 21030402194 in words is "twenty-one billion, thirty million, four hundred two thousand, one hundred ninety-four".