81367923 has 48 divisors (see below), whose sum is σ = 136187136. Its totient is φ = 42307200.

The previous prime is 81367907. The next prime is 81367931. The reversal of 81367923 is 32976318.

It is not a de Polignac number, because 81367923 - 2⁴ = 81367907 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (81367943) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 358336 + ... + 358562.

It is an arithmetic number, because the mean of its divisors is an integer number (2837232).

Almost surely, 2^81367923 is an apocalyptic number.

81367923 is a deficient number, since it is larger than the sum of its proper divisors (54819213).

81367923 is a wasteful number, since it uses less digits than its factorization.

81367923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 351 counting only the distinct ones).

The product of its digits is 54432, while the sum is 39.

The square root of 81367923 is about 9020.4170080989. The cubic root of 81367923 is about 433.3289888453.

The spelling of 81367923 in words is "eighty-one million, three hundred sixty-seven thousand, nine hundred twenty-three".