1085642731 has 4 divisors (see below), whose sum is σ = 1112121864. Its totient is φ = 1059163600.

The previous prime is 1085642699. The next prime is 1085642771. The reversal of 1085642731 is 1372465801.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1372465801 = 7 ⋅196066543.

It is a cyclic number.

It is not a de Polignac number, because 1085642731 - 2⁵ = 1085642699 is a prime.

It is a super-2 number, since 2×1085642731² = 2357240278746276722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1085642771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13239505 + ... + 13239586.

It is an arithmetic number, because the mean of its divisors is an integer number (278030466).

Almost surely, 2^1085642731 is an apocalyptic number.

1085642731 is a deficient number, since it is larger than the sum of its proper divisors (26479133).

1085642731 is an equidigital number, since it uses as much as digits as its factorization.

1085642731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26479132.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 1085642731 is about 32949.0930224187. The cubic root of 1085642731 is about 1027.7693047589.

The spelling of 1085642731 in words is "one billion, eighty-five million, six hundred forty-two thousand, seven hundred thirty-one".