81907426 has 8 divisors (see below), whose sum is σ = 127097820. Its totient is φ = 39541488.

The previous prime is 81907421. The next prime is 81907447. The reversal of 81907426 is 62470918.

It can be written as a sum of positive squares in 2 ways, for example, as 74805201 + 7102225 = 8649^2 + 2665^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (81907421) 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, 706041 + ... + 706156.

Almost surely, 2^81907426 is an apocalyptic number.

81907426 is a deficient number, since it is larger than the sum of its proper divisors (45190394).

81907426 is a wasteful number, since it uses less digits than its factorization.

81907426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412228.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 81907426 is about 9050.2721506041. The cubic root of 81907426 is about 434.2845967584.

The spelling of 81907426 in words is "eighty-one million, nine hundred seven thousand, four hundred twenty-six".