1816699945531 has 2 divisors, whose sum is σ = 1816699945532. Its totient is φ = 1816699945530.

The previous prime is 1816699945507. The next prime is 1816699945631. The reversal of 1816699945531 is 1355499966181.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1816699945531 - 2²³ = 1816691556923 is a prime.

It is a super-2 number, since 2×1816699945531² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1816699945031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 908349972765 + 908349972766.

It is an arithmetic number, because the mean of its divisors is an integer number (908349972766).

Almost surely, 2^{1816699945531} is an apocalyptic number.

1816699945531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1816699945531 is an equidigital number, since it uses as much as digits as its factorization.

1816699945531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62985600, while the sum is 67.

The spelling of 1816699945531 in words is "one trillion, eight hundred sixteen billion, six hundred ninety-nine million, nine hundred forty-five thousand, five hundred thirty-one".