85025311281 has 45 divisors (see below), whose sum is σ = 128436224763. Its totient is φ = 56055453840.

The previous prime is 85025311253. The next prime is 85025311309. The reversal of 85025311281 is 18211352058.

The square root of 85025311281 is 291591.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (85025311253) and next prime (85025311309).

It can be written as a sum of positive squares in only one way, i.e., 936910881 + 84088400400 = 30609^2 + 289980^2 .

It is not a de Polignac number, because 85025311281 - 2¹⁷ = 85025180209 is a prime.

It is a super-2 number, since 2×85025311281² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (85025311781) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 469753011 + ... + 469753191.

Almost surely, 2^85025311281 is an apocalyptic number.

85025311281 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

85025311281 is the 291591-st square number.

85025311281 is the 145796-th centered octagonal number.

It is an amenable number.

85025311281 is a deficient number, since it is larger than the sum of its proper divisors (43410913482).

85025311281 is an frugal number, since it uses more digits than its factorization.

85025311281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

Multiplying 85025311281 by its sum of digits (36), we get a square (3060911206116 = 1749546²).

The spelling of 85025311281 in words is "eighty-five billion, twenty-five million, three hundred eleven thousand, two hundred eighty-one".