3644495242781 has 2 divisors, whose sum is σ = 3644495242782. Its totient is φ = 3644495242780.

The previous prime is 3644495242771. The next prime is 3644495242807. The reversal of 3644495242781 is 1872425944463.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3179923498756 + 464571744025 = 1783234^2 + 681595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3644495242781 is a prime.

It is a super-2 number, since 2×3644495242781² (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 3644495242781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3644495242741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1822247621390 + 1822247621391.

It is an arithmetic number, because the mean of its divisors is an integer number (1822247621391).

Almost surely, 2^{3644495242781} is an apocalyptic number.

It is an amenable number.

3644495242781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3644495242781 is an equidigital number, since it uses as much as digits as its factorization.

3644495242781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46448640, while the sum is 59.

The spelling of 3644495242781 in words is "three trillion, six hundred forty-four billion, four hundred ninety-five million, two hundred forty-two thousand, seven hundred eighty-one".