1868431491 has 6 divisors (see below), whose sum is σ = 2698845500. Its totient is φ = 1245620988.

The previous prime is 1868431489. The next prime is 1868431511. The reversal of 1868431491 is 1941348681.

1868431491 is a `hidden beast` number, since 1 + 86 + 84 + 3 + 1 + 491 = 666.

It is not a de Polignac number, because 1868431491 - 2¹ = 1868431489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1868431991) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 103801741 + ... + 103801758.

Almost surely, 2^1868431491 is an apocalyptic number.

1868431491 is a deficient number, since it is larger than the sum of its proper divisors (830414009).

1868431491 is a wasteful number, since it uses less digits than its factorization.

1868431491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207603505 (or 207603502 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 1868431491 is about 43225.3570372762. The cubic root of 1868431491 is about 1231.6644114195.

The spelling of 1868431491 in words is "one billion, eight hundred sixty-eight million, four hundred thirty-one thousand, four hundred ninety-one".