21793190121 has 6 divisors (see below), whose sum is σ = 31479052410. Its totient is φ = 14528793408.

The previous prime is 21793190117. The next prime is 21793190141. The reversal of 21793190121 is 12109139712.

21793190121 is a `hidden beast` number, since 217 + 9 + 319 + 0 + 121 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12968654400 + 8824535721 = 113880^2 + 93939^2 .

It is not a de Polignac number, because 21793190121 - 2² = 21793190117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21793190141) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1210732776 + ... + 1210732793.

It is an arithmetic number, because the mean of its divisors is an integer number (5246508735).

Almost surely, 2^21793190121 is an apocalyptic number.

It is an amenable number.

21793190121 is a deficient number, since it is larger than the sum of its proper divisors (9685862289).

21793190121 is a wasteful number, since it uses less digits than its factorization.

21793190121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2421465575 (or 2421465572 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 36.

The spelling of 21793190121 in words is "twenty-one billion, seven hundred ninety-three million, one hundred ninety thousand, one hundred twenty-one".