78400511 has 8 divisors (see below), whose sum is σ = 89732640. Its totient is φ = 67101408.

The previous prime is 78400501. The next prime is 78400523. The reversal of 78400511 is 11500487.

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

It is a cyclic number.

It is not a de Polignac number, because 78400511 - 2²⁶ = 11291647 is a prime.

It is a super-2 number, since 2×78400511² = 12293280250122242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78400501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2936 + ... + 12861.

It is an arithmetic number, because the mean of its divisors is an integer number (11216580).

Almost surely, 2^78400511 is an apocalyptic number.

78400511 is a deficient number, since it is larger than the sum of its proper divisors (11332129).

78400511 is a wasteful number, since it uses less digits than its factorization.

78400511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16513.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 78400511 is about 8854.4063042081. The cubic root of 78400511 is about 427.9959220941.

Adding to 78400511 its reverse (11500487), we get a palindrome (89900998).

The spelling of 78400511 in words is "seventy-eight million, four hundred thousand, five hundred eleven".