2215957991 has 8 divisors (see below), whose sum is σ = 2393502384. Its totient is φ = 2039425920.

The previous prime is 2215957981. The next prime is 2215958033. The reversal of 2215957991 is 1997595122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2215957991 - 2¹⁸ = 2215695847 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2215957921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 248525 + ... + 257286.

It is an arithmetic number, because the mean of its divisors is an integer number (299187798).

Almost surely, 2^2215957991 is an apocalyptic number.

2215957991 is a deficient number, since it is larger than the sum of its proper divisors (177544393).

2215957991 is a wasteful number, since it uses less digits than its factorization.

2215957991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506161.

The product of its digits is 510300, while the sum is 50.

The square root of 2215957991 is about 47073.9629837982. The cubic root of 2215957991 is about 1303.7285446135.

The spelling of 2215957991 in words is "two billion, two hundred fifteen million, nine hundred fifty-seven thousand, nine hundred ninety-one".