78372953566 has 4 divisors (see below), whose sum is σ = 117559430352. Its totient is φ = 39186476782.

The previous prime is 78372953557. The next prime is 78372953579. The reversal of 78372953566 is 66535927387.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×78372953566² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19593238390 + ... + 19593238393.

It is an arithmetic number, because the mean of its divisors is an integer number (29389857588).

Almost surely, 2^78372953566 is an apocalyptic number.

78372953566 is a deficient number, since it is larger than the sum of its proper divisors (39186476786).

78372953566 is a wasteful number, since it uses less digits than its factorization.

78372953566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39186476785.

The product of its digits is 57153600, while the sum is 61.

The spelling of 78372953566 in words is "seventy-eight billion, three hundred seventy-two million, nine hundred fifty-three thousand, five hundred sixty-six".