409155891 has 4 divisors (see below), whose sum is σ = 545541192. Its totient is φ = 272770592.

The previous prime is 409155883. The next prime is 409155907. The reversal of 409155891 is 198551904.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 409155891 - 2³ = 409155883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (409155841) 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, 68192646 + ... + 68192651.

It is an arithmetic number, because the mean of its divisors is an integer number (136385298).

Almost surely, 2^409155891 is an apocalyptic number.

409155891 is a deficient number, since it is larger than the sum of its proper divisors (136385301).

409155891 is a wasteful number, since it uses less digits than its factorization.

409155891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136385300.

The product of its (nonzero) digits is 64800, while the sum is 42.

The square root of 409155891 is about 20227.6022058968. The cubic root of 409155891 is about 742.3857085813.

The spelling of 409155891 in words is "four hundred nine million, one hundred fifty-five thousand, eight hundred ninety-one".