78220426 has 8 divisors (see below), whose sum is σ = 117926820. Its totient is φ = 38911488.

The previous prime is 78220379. The next prime is 78220433. The reversal of 78220426 is 62402287.

It can be written as a sum of positive squares in 2 ways, for example, as 66667225 + 11553201 = 8165^2 + 3399^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×78220426² = 12236870087242952, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98871 + ... + 99658.

Almost surely, 2^78220426 is an apocalyptic number.

78220426 is a deficient number, since it is larger than the sum of its proper divisors (39706394).

78220426 is a wasteful number, since it uses less digits than its factorization.

78220426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198728.

The product of its (nonzero) digits is 10752, while the sum is 31.

The square root of 78220426 is about 8844.2312271898. The cubic root of 78220426 is about 427.6679704264.

The spelling of 78220426 in words is "seventy-eight million, two hundred twenty thousand, four hundred twenty-six".