78420720897 has 12 divisors (see below), whose sum is σ = 119236184080. Its totient is φ = 49528876248.

The previous prime is 78420720893. The next prime is 78420720941. The reversal of 78420720897 is 79802702487.

78420720897 is a `hidden beast` number, since 7 + 8 + 420 + 7 + 208 + 9 + 7 = 666.

It is not a de Polignac number, because 78420720897 - 2² = 78420720893 is a prime.

It is a super-2 number, since 2×78420720897² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78420720893) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 229300183 + ... + 229300524.

Almost surely, 2^78420720897 is an apocalyptic number.

It is an amenable number.

78420720897 is a deficient number, since it is larger than the sum of its proper divisors (40815463183).

78420720897 is a wasteful number, since it uses less digits than its factorization.

78420720897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458600732 (or 458600729 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 54.

The spelling of 78420720897 in words is "seventy-eight billion, four hundred twenty million, seven hundred twenty thousand, eight hundred ninety-seven".