78615651533 has 2 divisors, whose sum is σ = 78615651534. Its totient is φ = 78615651532.

The previous prime is 78615651523. The next prime is 78615651557. The reversal of 78615651533 is 33515651687.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46754115529 + 31861536004 = 216227^2 + 178498^2 .

It is a cyclic number.

It is not a de Polignac number, because 78615651533 - 2¹⁴ = 78615635149 is a prime.

It is a super-3 number, since 3×78615651533³ (a number of 34 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78615651523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39307825766 + 39307825767.

It is an arithmetic number, because the mean of its divisors is an integer number (39307825767).

Almost surely, 2^78615651533 is an apocalyptic number.

It is an amenable number.

78615651533 is a deficient number, since it is larger than the sum of its proper divisors (1).

78615651533 is an equidigital number, since it uses as much as digits as its factorization.

78615651533 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2268000, while the sum is 50.

The spelling of 78615651533 in words is "seventy-eight billion, six hundred fifteen million, six hundred fifty-one thousand, five hundred thirty-three".