311906143 has 2 divisors, whose sum is σ = 311906144. Its totient is φ = 311906142.

The previous prime is 311906137. The next prime is 311906171. The reversal of 311906143 is 341609113.

It is an a-pointer prime, because the next prime (311906171) can be obtained adding 311906143 to its sum of digits (28).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311906143 is a prime.

It is a super-2 number, since 2×311906143² = 194570884082272898, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311906173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155953071 + 155953072.

It is an arithmetic number, because the mean of its divisors is an integer number (155953072).

Almost surely, 2^311906143 is an apocalyptic number.

311906143 is a deficient number, since it is larger than the sum of its proper divisors (1).

311906143 is an equidigital number, since it uses as much as digits as its factorization.

311906143 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 311906143 is about 17660.8647296784. The cubic root of 311906143 is about 678.1742713263.

The spelling of 311906143 in words is "three hundred eleven million, nine hundred six thousand, one hundred forty-three".