81284503 has 2 divisors, whose sum is σ = 81284504. Its totient is φ = 81284502.

The previous prime is 81284471. The next prime is 81284519. The reversal of 81284503 is 30548218.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81284503 - 2⁵ = 81284471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81281503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40642251 + 40642252.

It is an arithmetic number, because the mean of its divisors is an integer number (40642252).

Almost surely, 2^81284503 is an apocalyptic number.

81284503 is a deficient number, since it is larger than the sum of its proper divisors (1).

81284503 is an equidigital number, since it uses as much as digits as its factorization.

81284503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 81284503 is about 9015.7918676065. The cubic root of 81284503 is about 433.1808524001.

The spelling of 81284503 in words is "eighty-one million, two hundred eighty-four thousand, five hundred three".