85217557 has 8 divisors (see below), whose sum is σ = 87521112. Its totient is φ = 82924800.

The previous prime is 85217519. The next prime is 85217563. The reversal of 85217557 is 75571258.

It can be written as a sum of positive squares in 4 ways, for example, as 6522916 + 78694641 = 2554^2 + 8871^2 .

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 85217557 - 2²³ = 76828949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85217567) 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, 14793 + ... + 19729.

It is an arithmetic number, because the mean of its divisors is an integer number (10940139).

Almost surely, 2^85217557 is an apocalyptic number.

It is an amenable number.

85217557 is a deficient number, since it is larger than the sum of its proper divisors (2303555).

85217557 is a wasteful number, since it uses less digits than its factorization.

85217557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5399.

The product of its digits is 98000, while the sum is 40.

The square root of 85217557 is about 9231.3356021759. The cubic root of 85217557 is about 440.0577696187.

The spelling of 85217557 in words is "eighty-five million, two hundred seventeen thousand, five hundred fifty-seven".