78307444 has 6 divisors (see below), whose sum is σ = 137038034. Its totient is φ = 39153720.

The previous prime is 78307441. The next prime is 78307459. The reversal of 78307444 is 44470387.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 77651344 + 656100 = 8812^2 + 810^2 .

It is a super-2 number, since 2×78307444² = 12264111571626272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78307441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9788427 + ... + 9788434.

Almost surely, 2^78307444 is an apocalyptic number.

It is an amenable number.

78307444 is a deficient number, since it is larger than the sum of its proper divisors (58730590).

78307444 is a wasteful number, since it uses less digits than its factorization.

78307444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19576865 (or 19576863 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 37.

The square root of 78307444 is about 8849.1493376482. The cubic root of 78307444 is about 427.8265011399.

The spelling of 78307444 in words is "seventy-eight million, three hundred seven thousand, four hundred forty-four".