81453389 has 2 divisors, whose sum is σ = 81453390. Its totient is φ = 81453388.

The previous prime is 81453371. The next prime is 81453433. The reversal of 81453389 is 98335418.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45333289 + 36120100 = 6733^2 + 6010^2 .

It is a cyclic number.

It is not a de Polignac number, because 81453389 - 2¹² = 81449293 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81453989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40726694 + 40726695.

It is an arithmetic number, because the mean of its divisors is an integer number (40726695).

Almost surely, 2^81453389 is an apocalyptic number.

It is an amenable number.

81453389 is a deficient number, since it is larger than the sum of its proper divisors (1).

81453389 is an equidigital number, since it uses as much as digits as its factorization.

81453389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 41.

The square root of 81453389 is about 9025.1531288948. The cubic root of 81453389 is about 433.4806535917.

The spelling of 81453389 in words is "eighty-one million, four hundred fifty-three thousand, three hundred eighty-nine".