81526978 has 16 divisors (see below), whose sum is σ = 131918976. Its totient is φ = 37564560.

The previous prime is 81526961. The next prime is 81526979. The reversal of 81526978 is 87962518.

It is not an unprimeable number, because it can be changed into a prime (81526979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15463 + ... + 20053.

It is an arithmetic number, because the mean of its divisors is an integer number (8244936).

Almost surely, 2^81526978 is an apocalyptic number.

81526978 is a deficient number, since it is larger than the sum of its proper divisors (50391998).

81526978 is a wasteful number, since it uses less digits than its factorization.

81526978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5289.

The product of its digits is 241920, while the sum is 46.

The square root of 81526978 is about 9029.2290922315. The cubic root of 81526978 is about 433.6111568833.

The spelling of 81526978 in words is "eighty-one million, five hundred twenty-six thousand, nine hundred seventy-eight".