78420297123 has 36 divisors (see below), whose sum is σ = 135163646280. Its totient is φ = 44805777912.

The previous prime is 78420297089. The next prime is 78420297143. The reversal of 78420297123 is 32179202487.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It is not a de Polignac number, because 78420297123 - 2²² = 78416102819 is a prime.

It is a super-2 number, since 2×78420297123² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78420297143) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10181928 + ... + 10189626.

It is an arithmetic number, because the mean of its divisors is an integer number (3754545730).

Almost surely, 2^78420297123 is an apocalyptic number.

78420297123 is a deficient number, since it is larger than the sum of its proper divisors (56743349157).

78420297123 is an frugal number, since it uses more digits than its factorization.

78420297123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15421 (or 7709 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The spelling of 78420297123 in words is "seventy-eight billion, four hundred twenty million, two hundred ninety-seven thousand, one hundred twenty-three".