36809809921 has 4 divisors (see below), whose sum is σ = 37099651072. Its totient is φ = 36519968772.

The previous prime is 36809809903. The next prime is 36809809943. The reversal of 36809809921 is 12990890863.

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 a cyclic number.

It is not a de Polignac number, because 36809809921 - 2⁹ = 36809809409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (36809809901) 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, 144920385 + ... + 144920638.

It is an arithmetic number, because the mean of its divisors is an integer number (9274912768).

Almost surely, 2^36809809921 is an apocalyptic number.

It is an amenable number.

36809809921 is a deficient number, since it is larger than the sum of its proper divisors (289841151).

36809809921 is a wasteful number, since it uses less digits than its factorization.

36809809921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289841150.

The product of its (nonzero) digits is 1679616, while the sum is 55.

The spelling of 36809809921 in words is "thirty-six billion, eight hundred nine million, eight hundred nine thousand, nine hundred twenty-one".