81462989 has 2 divisors, whose sum is σ = 81462990. Its totient is φ = 81462988.

The previous prime is 81462973. The next prime is 81462991. The reversal of 81462989 is 98926418.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72965764 + 8497225 = 8542^2 + 2915^2 .

It is a cyclic number.

It is not a de Polignac number, because 81462989 - 2⁴ = 81462973 is a prime.

Together with 81462991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81462949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40731494 + 40731495.

It is an arithmetic number, because the mean of its divisors is an integer number (40731495).

Almost surely, 2^81462989 is an apocalyptic number.

It is an amenable number.

81462989 is a deficient number, since it is larger than the sum of its proper divisors (1).

81462989 is an equidigital number, since it uses as much as digits as its factorization.

81462989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 47.

The square root of 81462989 is about 9025.6849601568. The cubic root of 81462989 is about 433.4976827616.

The spelling of 81462989 in words is "eighty-one million, four hundred sixty-two thousand, nine hundred eighty-nine".