78356647021041 has 81 divisors (see below), whose sum is σ = 120771882245313. Its totient is φ = 48947626598400.

The previous prime is 78356647020991. The next prime is 78356647021043. The reversal of 78356647021041 is 14012074665387.

The square root of 78356647021041 is 8851929.

It is a perfect power (a square), and thus also a powerful number.

78356647021041 is a `hidden beast` number, since 7 + 8 + 3 + 5 + 66 + 470 + 2 + 104 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 31314936200625 + 47041710820416 = 5595975^2 + 6858696^2 .

It is not a de Polignac number, because 78356647021041 - 2⁷ = 78356647020913 is a prime.

It is a super-2 number, since 2×78356647021041² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78356647021043) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 48942314641 + ... + 48942316241.

Almost surely, 2^{78356647021041} is an apocalyptic number.

78356647021041 is the 8851929-th square number.

78356647021041 is the 4425965-th centered octagonal number.

It is an amenable number.

78356647021041 is a deficient number, since it is larger than the sum of its proper divisors (42415235224272).

78356647021041 is an frugal number, since it uses more digits than its factorization.

78356647021041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3440 (or 1720 counting only the distinct ones).

The product of its (nonzero) digits is 6773760, while the sum is 54.

The spelling of 78356647021041 in words is "seventy-eight trillion, three hundred fifty-six billion, six hundred forty-seven million, twenty-one thousand, forty-one".