21112193691 has 36 divisors (see below), whose sum is σ = 33294858480. Its totient is φ = 12874165920.

The previous prime is 21112193689. The next prime is 21112193771. The reversal of 21112193691 is 19639121112.

It is not a de Polignac number, because 21112193691 - 2¹ = 21112193689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21112193891) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 17815 + ... + 206256.

It is an arithmetic number, because the mean of its divisors is an integer number (924857180).

Almost surely, 2^21112193691 is an apocalyptic number.

21112193691 is a deficient number, since it is larger than the sum of its proper divisors (12182664789).

21112193691 is a wasteful number, since it uses less digits than its factorization.

21112193691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224144 (or 224122 counting only the distinct ones).

The product of its digits is 5832, while the sum is 36.

The spelling of 21112193691 in words is "twenty-one billion, one hundred twelve million, one hundred ninety-three thousand, six hundred ninety-one".