215215720691 has 8 divisors (see below), whose sum is σ = 218017126080. Its totient is φ = 212416244352.

The previous prime is 215215720669. The next prime is 215215720697. The reversal of 215215720691 is 196027512512.

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 215215720691 - 2⁶ = 215215720627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215215720697) 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, 257000 + ... + 704613.

It is an arithmetic number, because the mean of its divisors is an integer number (27252140760).

Almost surely, 2^215215720691 is an apocalyptic number.

215215720691 is a deficient number, since it is larger than the sum of its proper divisors (2801405389).

215215720691 is an equidigital number, since it uses as much as digits as its factorization.

215215720691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 964525.

The product of its (nonzero) digits is 75600, while the sum is 41.

The spelling of 215215720691 in words is "two hundred fifteen billion, two hundred fifteen million, seven hundred twenty thousand, six hundred ninety-one".