78211306 has 4 divisors (see below), whose sum is σ = 117316962. Its totient is φ = 39105652.

The previous prime is 78211291. The next prime is 78211319. The reversal of 78211306 is 60311287.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60311287 = 41 ⋅1471007.

It can be written as a sum of positive squares in only one way, i.e., 59367025 + 18844281 = 7705^2 + 4341^2 .

It is a super-2 number, since 2×78211306² = 12234016772451272, which contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 19552825 + ... + 19552828.

Almost surely, 2^78211306 is an apocalyptic number.

78211306 is a deficient number, since it is larger than the sum of its proper divisors (39105656).

78211306 is a wasteful number, since it uses less digits than its factorization.

78211306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39105655.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 78211306 is about 8843.7156218413. The cubic root of 78211306 is about 427.6513486662.

The spelling of 78211306 in words is "seventy-eight million, two hundred eleven thousand, three hundred six".