215694756161 has 8 divisors (see below), whose sum is σ = 228603788424. Its totient is φ = 202810291200.

The previous prime is 215694756143. The next prime is 215694756169. The reversal of 215694756161 is 161657496512.

It can be written as a sum of positive squares in 4 ways, for example, as 185403442225 + 30291313936 = 430585^2 + 174044^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215694756161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (215694756169) 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, 6123740 + ... + 6158861.

It is an arithmetic number, because the mean of its divisors is an integer number (28575473553).

Almost surely, 2^215694756161 is an apocalyptic number.

It is an amenable number.

215694756161 is a deficient number, since it is larger than the sum of its proper divisors (12909032263).

215694756161 is a wasteful number, since it uses less digits than its factorization.

215694756161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12283651.

The product of its digits is 2721600, while the sum is 53.

The spelling of 215694756161 in words is "two hundred fifteen billion, six hundred ninety-four million, seven hundred fifty-six thousand, one hundred sixty-one".