21000120197 has 8 divisors (see below), whose sum is σ = 24036896256. Its totient is φ = 17972533872.

The previous prime is 21000120187. The next prime is 21000120217. The reversal of 21000120197 is 79102100012.

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

It is a cyclic number.

It is not a de Polignac number, because 21000120197 - 2²² = 20995925893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000120157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2292533 + ... + 2301674.

It is an arithmetic number, because the mean of its divisors is an integer number (3004612032).

Almost surely, 2^21000120197 is an apocalyptic number.

It is an amenable number.

21000120197 is a deficient number, since it is larger than the sum of its proper divisors (3036776059).

21000120197 is an equidigital number, since it uses as much as digits as its factorization.

21000120197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4594867.

The product of its (nonzero) digits is 252, while the sum is 23.

The spelling of 21000120197 in words is "twenty-one billion, one hundred twenty thousand, one hundred ninety-seven".