78123801 has 32 divisors (see below), whose sum is σ = 130775040. Its totient is φ = 40449024.

The previous prime is 78123739. The next prime is 78123827. The reversal of 78123801 is 10832187.

It is a happy number.

It is not a de Polignac number, because 78123801 - 2⁹ = 78123289 is a prime.

It is a super-2 number, since 2×78123801² = 12206656565375202, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78128801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4921 + ... + 13433.

It is an arithmetic number, because the mean of its divisors is an integer number (4086720).

Almost surely, 2^78123801 is an apocalyptic number.

It is an amenable number.

78123801 is a deficient number, since it is larger than the sum of its proper divisors (52651239).

78123801 is a wasteful number, since it uses less digits than its factorization.

78123801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8565.

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 78123801 is about 8838.7669388892. The cubic root of 78123801 is about 427.4917997127.

Adding to 78123801 its reverse (10832187), we get a palindrome (88955988).

It can be divided in two parts, 781 and 23801, that multiplied together give a palindrome (18588581).

The spelling of 78123801 in words is "seventy-eight million, one hundred twenty-three thousand, eight hundred one".