78153583991 has 4 divisors (see below), whose sum is σ = 89318381712. Its totient is φ = 66988786272.

The previous prime is 78153583969. The next prime is 78153584023. The reversal of 78153583991 is 19938535187.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 78153583991 - 2⁶ = 78153583927 is a prime.

It is a super-2 number, since 2×78153583991² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78153583991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78153583951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5582398850 + ... + 5582398863.

It is an arithmetic number, because the mean of its divisors is an integer number (22329595428).

Almost surely, 2^78153583991 is an apocalyptic number.

78153583991 is a deficient number, since it is larger than the sum of its proper divisors (11164797721).

78153583991 is a wasteful number, since it uses less digits than its factorization.

78153583991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11164797720.

The product of its digits is 8164800, while the sum is 59.

The spelling of 78153583991 in words is "seventy-eight billion, one hundred fifty-three million, five hundred eighty-three thousand, nine hundred ninety-one".