1645741645731 has 24 divisors (see below), whose sum is σ = 2482508770560. Its totient is φ = 1048624709616.

The previous prime is 1645741645721. The next prime is 1645741645733. The reversal of 1645741645731 is 1375461475461.

It is a happy number.

1645741645731 is a `hidden beast` number, since 1 + 6 + 4 + 5 + 7 + 4 + 1 + 64 + 573 + 1 = 666.

It is not a de Polignac number, because 1645741645731 - 2¹³ = 1645741637539 is a prime.

It is a super-2 number, since 2×1645741645731² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1645741645733) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2896831 + ... + 3418056.

It is an arithmetic number, because the mean of its divisors is an integer number (103437865440).

Almost surely, 2^{1645741645731} is an apocalyptic number.

1645741645731 is a deficient number, since it is larger than the sum of its proper divisors (836767124829).

1645741645731 is a wasteful number, since it uses less digits than its factorization.

1645741645731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6316175 (or 6316172 counting only the distinct ones).

The product of its digits is 8467200, while the sum is 54.

The spelling of 1645741645731 in words is "one trillion, six hundred forty-five billion, seven hundred forty-one million, six hundred forty-five thousand, seven hundred thirty-one".