291148906 has 4 divisors (see below), whose sum is σ = 436723362. Its totient is φ = 145574452.

The previous prime is 291148889. The next prime is 291148939. The reversal of 291148906 is 609841192.

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

It can be written as a sum of positive squares in only one way, i.e., 281937681 + 9211225 = 16791^2 + 3035^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72787225 + ... + 72787228.

Almost surely, 2^291148906 is an apocalyptic number.

291148906 is a deficient number, since it is larger than the sum of its proper divisors (145574456).

291148906 is a wasteful number, since it uses less digits than its factorization.

291148906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145574455.

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 291148906 is about 17063.0860631950. The cubic root of 291148906 is about 662.7835499654.

The spelling of 291148906 in words is "two hundred ninety-one million, one hundred forty-eight thousand, nine hundred six".