85215769 has 2 divisors, whose sum is σ = 85215770. Its totient is φ = 85215768.

The previous prime is 85215751. The next prime is 85215797. The reversal of 85215769 is 96751258.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84879369 + 336400 = 9213^2 + 580^2 .

It is a cyclic number.

It is not a de Polignac number, because 85215769 - 2⁵ = 85215737 is a prime.

It is a super-2 number, since 2×85215769² = 14523454572522722, which contains 22 as substring.

It is equal to p_4955479 and since 85215769 and 4955479 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (85215749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42607884 + 42607885.

It is an arithmetic number, because the mean of its divisors is an integer number (42607885).

Almost surely, 2^85215769 is an apocalyptic number.

It is an amenable number.

85215769 is a deficient number, since it is larger than the sum of its proper divisors (1).

85215769 is an equidigital number, since it uses as much as digits as its factorization.

85215769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 43.

The square root of 85215769 is about 9231.2387576099. The cubic root of 85215769 is about 440.0546918930.

The spelling of 85215769 in words is "eighty-five million, two hundred fifteen thousand, seven hundred sixty-nine".