81574083506 has 8 divisors (see below), whose sum is σ = 124964553600. Its totient is φ = 39919232308.

The previous prime is 81574083497. The next prime is 81574083511. The reversal of 81574083506 is 60538047518.

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

It is a super-2 number, since 2×81574083506² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

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, 433904606 + ... + 433904793.

It is an arithmetic number, because the mean of its divisors is an integer number (15620569200).

Almost surely, 2^81574083506 is an apocalyptic number.

81574083506 is a deficient number, since it is larger than the sum of its proper divisors (43390470094).

81574083506 is a wasteful number, since it uses less digits than its factorization.

81574083506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 867809448.

The product of its (nonzero) digits is 806400, while the sum is 47.

The spelling of 81574083506 in words is "eighty-one billion, five hundred seventy-four million, eighty-three thousand, five hundred six".