81950774 has 4 divisors (see below), whose sum is σ = 122926164. Its totient is φ = 40975386.

The previous prime is 81950731. The next prime is 81950777. The reversal of 81950774 is 47705918.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81950777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20487692 + ... + 20487695.

It is an arithmetic number, because the mean of its divisors is an integer number (30731541).

Almost surely, 2^81950774 is an apocalyptic number.

81950774 is a deficient number, since it is larger than the sum of its proper divisors (40975390).

81950774 is a wasteful number, since it uses less digits than its factorization.

81950774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40975389.

The product of its (nonzero) digits is 70560, while the sum is 41.

The square root of 81950774 is about 9052.6666789405. Note that the first 4 decimals coincide. The cubic root of 81950774 is about 434.3611956278.

The spelling of 81950774 in words is "eighty-one million, nine hundred fifty thousand, seven hundred seventy-four".