3731816861 has 4 divisors (see below), whose sum is σ = 3894069792. Its totient is φ = 3569563932.

The previous prime is 3731816849. The next prime is 3731816911. The reversal of 3731816861 is 1686181373.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1686181373 = 163 ⋅10344671.

It is a cyclic number.

It is not a de Polignac number, because 3731816861 - 2¹⁰ = 3731815837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3731815861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81126431 + ... + 81126476.

It is an arithmetic number, because the mean of its divisors is an integer number (973517448).

Almost surely, 2^3731816861 is an apocalyptic number.

It is an amenable number.

3731816861 is a deficient number, since it is larger than the sum of its proper divisors (162252931).

3731816861 is a wasteful number, since it uses less digits than its factorization.

3731816861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162252930.

The product of its digits is 145152, while the sum is 44.

The square root of 3731816861 is about 61088.5984533939. The cubic root of 3731816861 is about 1551.1011060485.

The spelling of 3731816861 in words is "three billion, seven hundred thirty-one million, eight hundred sixteen thousand, eight hundred sixty-one".