291621151 has 4 divisors (see below), whose sum is σ = 298733904. Its totient is φ = 284508400.

The previous prime is 291621149. The next prime is 291621173. The reversal of 291621151 is 151126192.

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 291621151 - 2¹ = 291621149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (291021151) 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, 3556315 + ... + 3556396.

It is an arithmetic number, because the mean of its divisors is an integer number (74683476).

Almost surely, 2^291621151 is an apocalyptic number.

291621151 is a deficient number, since it is larger than the sum of its proper divisors (7112753).

291621151 is an equidigital number, since it uses as much as digits as its factorization.

291621151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7112752.

The product of its digits is 1080, while the sum is 28.

The square root of 291621151 is about 17076.9186623348. The cubic root of 291621151 is about 663.1417024850.

The spelling of 291621151 in words is "two hundred ninety-one million, six hundred twenty-one thousand, one hundred fifty-one".