3914778402581 has 2 divisors, whose sum is σ = 3914778402582. Its totient is φ = 3914778402580.

The previous prime is 3914778402569. The next prime is 3914778402593. The reversal of 3914778402581 is 1852048774193.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (3914778402569) and next prime (3914778402593).

It can be written as a sum of positive squares in only one way, i.e., 2314022058481 + 1600756344100 = 1521191^2 + 1265210^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3914778402581 is a prime.

It is a super-2 number, since 2×3914778402581² (a number of 26 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 3914778402581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3914778402541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1957389201290 + 1957389201291.

It is an arithmetic number, because the mean of its divisors is an integer number (1957389201291).

Almost surely, 2^{3914778402581} is an apocalyptic number.

It is an amenable number.

3914778402581 is a deficient number, since it is larger than the sum of its proper divisors (1).

3914778402581 is an equidigital number, since it uses as much as digits as its factorization.

3914778402581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13547520, while the sum is 59.

The spelling of 3914778402581 in words is "three trillion, nine hundred fourteen billion, seven hundred seventy-eight million, four hundred two thousand, five hundred eighty-one".