1661855031 has 6 divisors (see below), whose sum is σ = 2400457280. Its totient is φ = 1107903348.

The previous prime is 1661855021. The next prime is 1661855047. The reversal of 1661855031 is 1305581661.

1661855031 is a `hidden beast` number, since 1 + 6 + 618 + 5 + 5 + 0 + 31 = 666.

It is not a de Polignac number, because 1661855031 - 2¹³ = 1661846839 is a prime.

It is a super-2 number, since 2×1661855031² = 5523524288120021922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661855021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92325271 + ... + 92325288.

Almost surely, 2^1661855031 is an apocalyptic number.

1661855031 is a deficient number, since it is larger than the sum of its proper divisors (738602249).

1661855031 is a wasteful number, since it uses less digits than its factorization.

1661855031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184650565 (or 184650562 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 1661855031 is about 40765.8561911804. The cubic root of 1661855031 is about 1184.4890367716.

The spelling of 1661855031 in words is "one billion, six hundred sixty-one million, eight hundred fifty-five thousand, thirty-one".