65699409 has 4 divisors (see below), whose sum is σ = 87599216. Its totient is φ = 43799604.

The previous prime is 65699371. The next prime is 65699411. The reversal of 65699409 is 90499656.

It is a happy number.

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.

It is not a de Polignac number, because 65699409 - 2²⁴ = 48922193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65699479) 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, 10949899 + ... + 10949904.

It is an arithmetic number, because the mean of its divisors is an integer number (21899804).

Almost surely, 2^65699409 is an apocalyptic number.

It is an amenable number.

65699409 is a deficient number, since it is larger than the sum of its proper divisors (21899807).

65699409 is a wasteful number, since it uses less digits than its factorization.

65699409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21899806.

The product of its (nonzero) digits is 524880, while the sum is 48.

The square root of 65699409 is about 8105.5171950962. The cubic root of 65699409 is about 403.5095529555.

The spelling of 65699409 in words is "sixty-five million, six hundred ninety-nine thousand, four hundred nine".