78999973 has 8 divisors (see below), whose sum is σ = 88011000. Its totient is φ = 70408128.

The previous prime is 78999961. The next prime is 78999979. The reversal of 78999973 is 37999987.

It can be written as a sum of positive squares in 4 ways, for example, as 4919524 + 74080449 = 2218^2 + 8607^2 .

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 78999973 - 2¹⁷ = 78868901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78999979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104398 + ... + 105151.

It is an arithmetic number, because the mean of its divisors is an integer number (11001375).

Almost surely, 2^78999973 is an apocalyptic number.

It is an amenable number.

78999973 is a deficient number, since it is larger than the sum of its proper divisors (9011027).

78999973 is a wasteful number, since it uses less digits than its factorization.

78999973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209591.

The product of its digits is 7715736, while the sum is 61.

The square root of 78999973 is about 8888.1928984468. The cubic root of 78999973 is about 429.0839938196.

The spelling of 78999973 in words is "seventy-eight million, nine hundred ninety-nine thousand, nine hundred seventy-three".