72781012 has 12 divisors (see below), whose sum is σ = 134859060. Its totient is φ = 34249856.

The previous prime is 72781003. The next prime is 72781013. The reversal of 72781012 is 21018727.

It can be written as a sum of positive squares in 2 ways, for example, as 64738116 + 8042896 = 8046^2 + 2836^2 .

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72781013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535087 + ... + 535222.

It is an arithmetic number, because the mean of its divisors is an integer number (11238255).

Almost surely, 2^72781012 is an apocalyptic number.

It is an amenable number.

72781012 is a deficient number, since it is larger than the sum of its proper divisors (62078048).

72781012 is a wasteful number, since it uses less digits than its factorization.

72781012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1070330 (or 1070328 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 72781012 is about 8531.1788165528. The cubic root of 72781012 is about 417.5155900330.

Adding to 72781012 its reverse (21018727), we get a palindrome (93799739).

The spelling of 72781012 in words is "seventy-two million, seven hundred eighty-one thousand, twelve".