78420540049 has 2 divisors, whose sum is σ = 78420540050. Its totient is φ = 78420540048.

The previous prime is 78420540013. The next prime is 78420540053. The reversal of 78420540049 is 94004502487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66131265600 + 12289274449 = 257160^2 + 110857^2 .

It is a cyclic number.

It is not a de Polignac number, because 78420540049 - 2²¹ = 78418442897 is a prime.

It is a super-2 number, since 2×78420540049² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78420539987 and 78420540014.

It is not a weakly prime, because it can be changed into another prime (78420540449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39210270024 + 39210270025.

It is an arithmetic number, because the mean of its divisors is an integer number (39210270025).

Almost surely, 2^78420540049 is an apocalyptic number.

It is an amenable number.

78420540049 is a deficient number, since it is larger than the sum of its proper divisors (1).

78420540049 is an equidigital number, since it uses as much as digits as its factorization.

78420540049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 43.

The spelling of 78420540049 in words is "seventy-eight billion, four hundred twenty million, five hundred forty thousand, forty-nine".