311778985 has 16 divisors (see below), whose sum is σ = 433443456. Its totient is φ = 210860928.

The previous prime is 311778977. The next prime is 311779003. The reversal of 311778985 is 589877113.

It is a cyclic number.

It is not a de Polignac number, because 311778985 - 2³ = 311778977 is a prime.

It is a super-2 number, since 2×311778985² = 194412270975260450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58459 + ... + 63568.

It is an arithmetic number, because the mean of its divisors is an integer number (27090216).

Almost surely, 2^311778985 is an apocalyptic number.

311778985 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

311778985 is a deficient number, since it is larger than the sum of its proper divisors (121664471).

311778985 is a wasteful number, since it uses less digits than its factorization.

311778985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122112.

The product of its digits is 423360, while the sum is 49.

The square root of 311778985 is about 17657.2643690918. The cubic root of 311778985 is about 678.0820993622.

The spelling of 311778985 in words is "three hundred eleven million, seven hundred seventy-eight thousand, nine hundred eighty-five".