71679649 has 4 divisors (see below), whose sum is σ = 72661636. Its totient is φ = 70697664.

The previous prime is 71679607. The next prime is 71679703. The reversal of 71679649 is 94697617.

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

It can be written as a sum of positive squares in 2 ways, for example, as 58247424 + 13432225 = 7632^2 + 3665^2 .

It is a cyclic number.

It is not a de Polignac number, because 71679649 - 2²¹ = 69582497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71674649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 490884 + ... + 491029.

It is an arithmetic number, because the mean of its divisors is an integer number (18165409).

Almost surely, 2^71679649 is an apocalyptic number.

It is an amenable number.

71679649 is a deficient number, since it is larger than the sum of its proper divisors (981987).

71679649 is an equidigital number, since it uses as much as digits as its factorization.

71679649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 981986.

The product of its digits is 571536, while the sum is 49.

The square root of 71679649 is about 8466.3834663922. The cubic root of 71679649 is about 415.3988501092.

The spelling of 71679649 in words is "seventy-one million, six hundred seventy-nine thousand, six hundred forty-nine".