77391045 has 20 divisors (see below), whose sum is σ = 138731340. Its totient is φ = 41275008.

The previous prime is 77391019. The next prime is 77391049. The reversal of 77391045 is 54019377.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 52620516 + 24770529 = 7254^2 + 4977^2 .

It is not a de Polignac number, because 77391045 - 2¹² = 77386949 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77391049) 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 19 ways as a sum of consecutive naturals, for example, 95140 + ... + 95949.

It is an arithmetic number, because the mean of its divisors is an integer number (6936567).

Almost surely, 2^77391045 is an apocalyptic number.

It is an amenable number.

77391045 is a deficient number, since it is larger than the sum of its proper divisors (61340295).

77391045 is a wasteful number, since it uses less digits than its factorization.

77391045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191106 (or 191097 counting only the distinct ones).

The product of its (nonzero) digits is 26460, while the sum is 36.

The square root of 77391045 is about 8797.2180261717. The cubic root of 77391045 is about 426.1510573202.

The spelling of 77391045 in words is "seventy-seven million, three hundred ninety-one thousand, forty-five".