81612203 has 2 divisors, whose sum is σ = 81612204. Its totient is φ = 81612202.

The previous prime is 81612187. The next prime is 81612227. The reversal of 81612203 is 30221618.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81612203 - 2⁴ = 81612187 is a prime.

It is not a weakly prime, because it can be changed into another prime (81612283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40806101 + 40806102.

It is an arithmetic number, because the mean of its divisors is an integer number (40806102).

Almost surely, 2^81612203 is an apocalyptic number.

81612203 is a deficient number, since it is larger than the sum of its proper divisors (1).

81612203 is an equidigital number, since it uses as much as digits as its factorization.

81612203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 81612203 is about 9033.9472546612. The cubic root of 81612203 is about 433.7621974440.

The spelling of 81612203 in words is "eighty-one million, six hundred twelve thousand, two hundred three".