72191899 has 12 divisors (see below), whose sum is σ = 78909600. Its totient is φ = 66010464.

The previous prime is 72191891. The next prime is 72191909. The reversal of 72191899 is 99819127.

It is a happy number.

It is not a de Polignac number, because 72191899 - 2³ = 72191891 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 (72191891) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16462 + ... + 20380.

It is an arithmetic number, because the mean of its divisors is an integer number (6575800).

Almost surely, 2^72191899 is an apocalyptic number.

72191899 is a deficient number, since it is larger than the sum of its proper divisors (6717701).

72191899 is a wasteful number, since it uses less digits than its factorization.

72191899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4054 (or 4041 counting only the distinct ones).

The product of its digits is 81648, while the sum is 46.

The square root of 72191899 is about 8496.5816067404. The cubic root of 72191899 is about 416.3860348901.

The spelling of 72191899 in words is "seventy-two million, one hundred ninety-one thousand, eight hundred ninety-nine".