247222991 has 4 divisors (see below), whose sum is σ = 247714992. Its totient is φ = 246730992.

The previous prime is 247222979. The next prime is 247223023. The reversal of 247222991 is 199222742.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-247222991 is a prime.

It is a super-2 number, since 2×247222991² = 122238414557972162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247222901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 245246 + ... + 246251.

It is an arithmetic number, because the mean of its divisors is an integer number (61928748).

Almost surely, 2^247222991 is an apocalyptic number.

247222991 is a deficient number, since it is larger than the sum of its proper divisors (492001).

247222991 is an equidigital number, since it uses as much as digits as its factorization.

247222991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492000.

The product of its digits is 36288, while the sum is 38.

The square root of 247222991 is about 15723.3263338264. The cubic root of 247222991 is about 627.6192932038.

The spelling of 247222991 in words is "two hundred forty-seven million, two hundred twenty-two thousand, nine hundred ninety-one".