609071891 has 4 divisors (see below), whose sum is σ = 630074400. Its totient is φ = 588069384.

The previous prime is 609071887. The next prime is 609071893. The reversal of 609071891 is 198170906.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198170906 = 2 ⋅99085453.

It is a cyclic number.

It is not a de Polignac number, because 609071891 - 2² = 609071887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (609071893) 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, 10501211 + ... + 10501268.

It is an arithmetic number, because the mean of its divisors is an integer number (157518600).

Almost surely, 2^609071891 is an apocalyptic number.

609071891 is a deficient number, since it is larger than the sum of its proper divisors (21002509).

609071891 is a wasteful number, since it uses less digits than its factorization.

609071891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21002508.

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 609071891 is about 24679.3819006879. The cubic root of 609071891 is about 847.6622690015.

The spelling of 609071891 in words is "six hundred nine million, seventy-one thousand, eight hundred ninety-one".