1167787981 has 2 divisors, whose sum is σ = 1167787982. Its totient is φ = 1167787980.

The previous prime is 1167787967. The next prime is 1167788029. The reversal of 1167787981 is 1897877611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1131245956 + 36542025 = 33634^2 + 6045^2 .

It is a cyclic number.

It is not a de Polignac number, because 1167787981 - 2¹¹ = 1167785933 is a prime.

It is a super-2 number, since 2×1167787981² = 2727457537136112722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1167787931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 583893990 + 583893991.

It is an arithmetic number, because the mean of its divisors is an integer number (583893991).

Almost surely, 2^1167787981 is an apocalyptic number.

It is an amenable number.

1167787981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1167787981 is an equidigital number, since it uses as much as digits as its factorization.

1167787981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1185408, while the sum is 55.

The square root of 1167787981 is about 34172.9129721187. The cubic root of 1167787981 is about 1053.0637594505.

The spelling of 1167787981 in words is "one billion, one hundred sixty-seven million, seven hundred eighty-seven thousand, nine hundred eighty-one".