81422947 has 2 divisors, whose sum is σ = 81422948. Its totient is φ = 81422946.

The previous prime is 81422933. The next prime is 81422963. The reversal of 81422947 is 74922418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81422947 - 2⁷ = 81422819 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81422147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40711473 + 40711474.

It is an arithmetic number, because the mean of its divisors is an integer number (40711474).

Almost surely, 2^81422947 is an apocalyptic number.

81422947 is a deficient number, since it is larger than the sum of its proper divisors (1).

81422947 is an equidigital number, since it uses as much as digits as its factorization.

81422947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32256, while the sum is 37.

The square root of 81422947 is about 9023.4664625076. The cubic root of 81422947 is about 433.4266445341.

It can be divided in two parts, 81422 and 947, that added together give a square (82369 = 287²).

The spelling of 81422947 in words is "eighty-one million, four hundred twenty-two thousand, nine hundred forty-seven".