81674157049 has 4 divisors (see below), whose sum is σ = 81858523536. Its totient is φ = 81489790564.

The previous prime is 81674157001. The next prime is 81674157091. The reversal of 81674157049 is 94075147618.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81674157049 - 2³³ = 73084222457 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81674156987 and 81674157005.

It is not an unprimeable number, because it can be changed into a prime (81674157949) 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, 92182579 + ... + 92183464.

It is an arithmetic number, because the mean of its divisors is an integer number (20464630884).

Almost surely, 2^81674157049 is an apocalyptic number.

It is an amenable number.

81674157049 is a deficient number, since it is larger than the sum of its proper divisors (184366487).

81674157049 is a wasteful number, since it uses less digits than its factorization.

81674157049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184366486.

The product of its (nonzero) digits is 1693440, while the sum is 52.

The spelling of 81674157049 in words is "eighty-one billion, six hundred seventy-four million, one hundred fifty-seven thousand, forty-nine".