75198991 has 16 divisors (see below), whose sum is σ = 88084480. Its totient is φ = 62868960.

The previous prime is 75198953. The next prime is 75199021. The reversal of 75198991 is 19989157.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-75198991 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 (75198091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50386 + ... + 51856.

It is an arithmetic number, because the mean of its divisors is an integer number (5505280).

Almost surely, 2^75198991 is an apocalyptic number.

75198991 is a deficient number, since it is larger than the sum of its proper divisors (12885489).

75198991 is a wasteful number, since it uses less digits than its factorization.

75198991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1654.

The product of its digits is 204120, while the sum is 49.

The square root of 75198991 is about 8671.7351781521. The cubic root of 75198991 is about 422.0889710807.

The spelling of 75198991 in words is "seventy-five million, one hundred ninety-eight thousand, nine hundred ninety-one".