199021901 has 8 divisors (see below), whose sum is σ = 216299160. Its totient is φ = 182025792.

The previous prime is 199021883. The next prime is 199021919. The reversal of 199021901 is 109120991.

It is an interprime number because it is at equal distance from previous prime (199021883) and next prime (199021919).

It can be written as a sum of positive squares in 4 ways, for example, as 34515625 + 164506276 = 5875^2 + 12826^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-199021901 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199020901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68810 + ... + 71643.

It is an arithmetic number, because the mean of its divisors is an integer number (27037395).

Almost surely, 2^199021901 is an apocalyptic number.

It is an amenable number.

199021901 is a deficient number, since it is larger than the sum of its proper divisors (17277259).

199021901 is a wasteful number, since it uses less digits than its factorization.

199021901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140575.

The product of its (nonzero) digits is 1458, while the sum is 32.

The square root of 199021901 is about 14107.5122186727. The cubic root of 199021901 is about 583.8486630520.

The spelling of 199021901 in words is "one hundred ninety-nine million, twenty-one thousand, nine hundred one".