191972407 has 8 divisors (see below), whose sum is σ = 212294160. Its totient is φ = 172128960.

The previous prime is 191972399. The next prime is 191972419. The reversal of 191972407 is 704279191.

191972407 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 191972407 - 2³ = 191972399 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 191972407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191972437) 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, 118732 + ... + 120337.

It is an arithmetic number, because the mean of its divisors is an integer number (26536770).

Almost surely, 2^191972407 is an apocalyptic number.

191972407 is a deficient number, since it is larger than the sum of its proper divisors (20321753).

191972407 is a wasteful number, since it uses less digits than its factorization.

191972407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239153.

The product of its (nonzero) digits is 31752, while the sum is 40.

The square root of 191972407 is about 13855.4107481518. The cubic root of 191972407 is about 576.8721906931.

The spelling of 191972407 in words is "one hundred ninety-one million, nine hundred seventy-two thousand, four hundred seven".