81478570 has 8 divisors (see below), whose sum is σ = 146661444. Its totient is φ = 32591424.

The previous prime is 81478561. The next prime is 81478597. The reversal of 81478570 is 7587418.

It can be written as a sum of positive squares in 2 ways, for example, as 67914081 + 13564489 = 8241^2 + 3683^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4073919 + ... + 4073938.

Almost surely, 2^81478570 is an apocalyptic number.

81478570 is a deficient number, since it is larger than the sum of its proper divisors (65182874).

81478570 is a wasteful number, since it uses less digits than its factorization.

81478570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8147864.

The product of its (nonzero) digits is 62720, while the sum is 40.

The square root of 81478570 is about 9026.5480666753. The cubic root of 81478570 is about 433.5253186115.

The spelling of 81478570 in words is "eighty-one million, four hundred seventy-eight thousand, five hundred seventy".