81900743 has 8 divisors (see below), whose sum is σ = 83851200. Its totient is φ = 79959040.

The previous prime is 81900719. The next prime is 81900751. The reversal of 81900743 is 34700918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81900743 - 2⁸ = 81900487 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 (81900443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19163 + ... + 23043.

It is an arithmetic number, because the mean of its divisors is an integer number (10481400).

Almost surely, 2^81900743 is an apocalyptic number.

81900743 is a deficient number, since it is larger than the sum of its proper divisors (1950457).

81900743 is a wasteful number, since it uses less digits than its factorization.

81900743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4377.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 81900743 is about 9049.9029276562. The cubic root of 81900743 is about 434.2727850377.

The spelling of 81900743 in words is "eighty-one million, nine hundred thousand, seven hundred forty-three".