78261812 has 12 divisors (see below), whose sum is σ = 145014660. Its totient is φ = 36829056.

The previous prime is 78261811. The next prime is 78261839. The reversal of 78261812 is 21816287.

It can be written as a sum of positive squares in 2 ways, for example, as 21771556 + 56490256 = 4666^2 + 7516^2 .

It is a super-2 number, since 2×78261812² = 12249822435046688, which contains 22 as substring.

It is a hoax number, since the sum of its digits (35) 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 (78261811) 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, 575387 + ... + 575522.

It is an arithmetic number, because the mean of its divisors is an integer number (12084555).

Almost surely, 2^78261812 is an apocalyptic number.

It is an amenable number.

78261812 is a deficient number, since it is larger than the sum of its proper divisors (66752848).

78261812 is a wasteful number, since it uses less digits than its factorization.

78261812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150930 (or 1150928 counting only the distinct ones).

The product of its digits is 10752, while the sum is 35.

The square root of 78261812 is about 8846.5706349975. The cubic root of 78261812 is about 427.7433827234.

The spelling of 78261812 in words is "seventy-eight million, two hundred sixty-one thousand, eight hundred twelve".