78202011110021 has 4 divisors (see below), whose sum is σ = 78211073815500. Its totient is φ = 78192948404544.

The previous prime is 78202011109921. The next prime is 78202011110071. The reversal of 78202011110021 is 12001111020287.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 35509978950625 + 42692032159396 = 5959025^2 + 6533914^2 .

It is a cyclic number.

It is not a de Polignac number, because 78202011110021 - 2²⁶ = 78201944001157 is a prime.

It is a super-2 number, since 2×78202011110021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78202011110071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4531339796 + ... + 4531357053.

It is an arithmetic number, because the mean of its divisors is an integer number (19552768453875).

Almost surely, 2^{78202011110021} is an apocalyptic number.

It is an amenable number.

78202011110021 is a deficient number, since it is larger than the sum of its proper divisors (9062705479).

78202011110021 is an equidigital number, since it uses as much as digits as its factorization.

78202011110021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9062705478.

The product of its (nonzero) digits is 448, while the sum is 26.

The spelling of 78202011110021 in words is "seventy-eight trillion, two hundred two billion, eleven million, one hundred ten thousand, twenty-one".