81154547 has 2 divisors, whose sum is σ = 81154548. Its totient is φ = 81154546.

The previous prime is 81154519. The next prime is 81154573. The reversal of 81154547 is 74545118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81154547 - 2¹² = 81150451 is a prime.

It is not a weakly prime, because it can be changed into another prime (81154147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40577273 + 40577274.

It is an arithmetic number, because the mean of its divisors is an integer number (40577274).

Almost surely, 2^81154547 is an apocalyptic number.

81154547 is a deficient number, since it is larger than the sum of its proper divisors (1).

81154547 is an equidigital number, since it uses as much as digits as its factorization.

81154547 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22400, while the sum is 35.

The square root of 81154547 is about 9008.5818528778. The cubic root of 81154547 is about 432.9498757020.

The spelling of 81154547 in words is "eighty-one million, one hundred fifty-four thousand, five hundred forty-seven".