78409976 has 16 divisors (see below), whose sum is σ = 147343200. Its totient is φ = 39118464.

The previous prime is 78409973. The next prime is 78410021. The reversal of 78409976 is 67990487.

It is a happy number.

It is a super-2 number, since 2×78409976² = 12296248672641152, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78409973) 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, 6881 + ... + 14288.

It is an arithmetic number, because the mean of its divisors is an integer number (9208950).

Almost surely, 2^78409976 is an apocalyptic number.

It is an amenable number.

78409976 is a deficient number, since it is larger than the sum of its proper divisors (68933224).

78409976 is a wasteful number, since it uses less digits than its factorization.

78409976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21638 (or 21634 counting only the distinct ones).

The product of its (nonzero) digits is 762048, while the sum is 50.

The square root of 78409976 is about 8854.9407677296. The cubic root of 78409976 is about 428.0131448491.

The spelling of 78409976 in words is "seventy-eight million, four hundred nine thousand, nine hundred seventy-six".