144991809 has 16 divisors (see below), whose sum is σ = 215259840. Its totient is φ = 96455520.

The previous prime is 144991801. The next prime is 144991837. The reversal of 144991809 is 908199441.

It is not a de Polignac number, because 144991809 - 2³ = 144991801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (144991801) 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, 7789 + ... + 18725.

It is an arithmetic number, because the mean of its divisors is an integer number (13453740).

Almost surely, 2^144991809 is an apocalyptic number.

It is an amenable number.

144991809 is a deficient number, since it is larger than the sum of its proper divisors (70268031).

144991809 is a wasteful number, since it uses less digits than its factorization.

144991809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11437 (or 11431 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 45.

The square root of 144991809 is about 12041.2544612262. The cubic root of 144991809 is about 525.3488946174.

The spelling of 144991809 in words is "one hundred forty-four million, nine hundred ninety-one thousand, eight hundred nine".