81448390 has 8 divisors (see below), whose sum is σ = 146607120. Its totient is φ = 32579352.

The previous prime is 81448387. The next prime is 81448417. The reversal of 81448390 is 9384418.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4072410 + ... + 4072429.

It is an arithmetic number, because the mean of its divisors is an integer number (18325890).

Almost surely, 2^81448390 is an apocalyptic number.

81448390 is a deficient number, since it is larger than the sum of its proper divisors (65158730).

81448390 is a wasteful number, since it uses less digits than its factorization.

81448390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8144846.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 81448390 is about 9024.8761764359. The cubic root of 81448390 is about 433.4717854764.

The spelling of 81448390 in words is "eighty-one million, four hundred forty-eight thousand, three hundred ninety".