72780347 has 4 divisors (see below), whose sum is σ = 73010256. Its totient is φ = 72550440.

The previous prime is 72780329. The next prime is 72780353. The reversal of 72780347 is 74308727.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74308727 = 2579 ⋅28813.

It is a cyclic number.

It is not a de Polignac number, because 72780347 - 2⁶ = 72780283 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72780347.

It is not an unprimeable number, because it can be changed into a prime (72780307) 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, 114479 + ... + 115112.

It is an arithmetic number, because the mean of its divisors is an integer number (18252564).

Almost surely, 2^72780347 is an apocalyptic number.

72780347 is a deficient number, since it is larger than the sum of its proper divisors (229909).

72780347 is a wasteful number, since it uses less digits than its factorization.

72780347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229908.

The product of its (nonzero) digits is 65856, while the sum is 38.

The square root of 72780347 is about 8531.1398417796. The cubic root of 72780347 is about 417.5143184160.

The spelling of 72780347 in words is "seventy-two million, seven hundred eighty thousand, three hundred forty-seven".