145699009 has 4 divisors (see below), whose sum is σ = 145723840. Its totient is φ = 145674180.

The previous prime is 145698991. The next prime is 145699031. The reversal of 145699009 is 900996541.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 900996541 = 661 ⋅1363081.

It is a cyclic number.

It is not a de Polignac number, because 145699009 - 2⁷ = 145698881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145699709) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1852 + ... + 17170.

It is an arithmetic number, because the mean of its divisors is an integer number (36430960).

Almost surely, 2^145699009 is an apocalyptic number.

It is an amenable number.

145699009 is a deficient number, since it is larger than the sum of its proper divisors (24831).

145699009 is an equidigital number, since it uses as much as digits as its factorization.

145699009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24830.

The product of its (nonzero) digits is 87480, while the sum is 43.

The square root of 145699009 is about 12070.5844514671. The cubic root of 145699009 is about 526.2016423914.

The spelling of 145699009 in words is "one hundred forty-five million, six hundred ninety-nine thousand, nine".