81767954 has 4 divisors (see below), whose sum is σ = 122651934. Its totient is φ = 40883976.

The previous prime is 81767951. The next prime is 81767969. The reversal of 81767954 is 45976718.

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

It can be written as a sum of positive squares in only one way, i.e., 68973025 + 12794929 = 8305^2 + 3577^2 .

It is a super-2 number, since 2×81767954² = 13371996602692232, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81767899 and 81767908.

It is not an unprimeable number, because it can be changed into a prime (81767951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20441987 + ... + 20441990.

Almost surely, 2^81767954 is an apocalyptic number.

81767954 is a deficient number, since it is larger than the sum of its proper divisors (40883980).

81767954 is a wasteful number, since it uses less digits than its factorization.

81767954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40883979.

The product of its digits is 423360, while the sum is 47.

The square root of 81767954 is about 9042.5634639741. The cubic root of 81767954 is about 434.0379567134.

The spelling of 81767954 in words is "eighty-one million, seven hundred sixty-seven thousand, nine hundred fifty-four".