81490903 has 16 divisors (see below), whose sum is σ = 91840896. Its totient is φ = 71804160.

The previous prime is 81490901. The next prime is 81490919. The reversal of 81490903 is 30909418.

It is a cyclic number.

It is not a de Polignac number, because 81490903 - 2¹ = 81490901 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81490901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23425 + ... + 26677.

It is an arithmetic number, because the mean of its divisors is an integer number (5740056).

Almost surely, 2^81490903 is an apocalyptic number.

81490903 is a deficient number, since it is larger than the sum of its proper divisors (10349993).

81490903 is a wasteful number, since it uses less digits than its factorization.

81490903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3354.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 81490903 is about 9027.2311923424. The cubic root of 81490903 is about 433.5471910213.

The spelling of 81490903 in words is "eighty-one million, four hundred ninety thousand, nine hundred three".