81449119 has 4 divisors (see below), whose sum is σ = 82071000. Its totient is φ = 80827240.

The previous prime is 81449113. The next prime is 81449129. The reversal of 81449119 is 91194418.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81449119 - 2¹³ = 81440927 is a prime.

It is a super-2 number, since 2×81449119² = 13267917971752322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81449113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 310744 + ... + 311005.

It is an arithmetic number, because the mean of its divisors is an integer number (20517750).

Almost surely, 2^81449119 is an apocalyptic number.

81449119 is a deficient number, since it is larger than the sum of its proper divisors (621881).

81449119 is a wasteful number, since it uses less digits than its factorization.

81449119 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621880.

The product of its digits is 10368, while the sum is 37.

The square root of 81449119 is about 9024.9165647113. The cubic root of 81449119 is about 433.4730787289.

The spelling of 81449119 in words is "eighty-one million, four hundred forty-nine thousand, one hundred nineteen".