1645761355557 has 12 divisors (see below), whose sum is σ = 2411969810880. Its totient is φ = 997431124360.

The previous prime is 1645761355549. The next prime is 1645761355577. The reversal of 1645761355557 is 7555531675461.

It is not a de Polignac number, because 1645761355557 - 2³ = 1645761355549 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1645761355557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645761355577) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2266888557 + ... + 2266889282.

It is an arithmetic number, because the mean of its divisors is an integer number (200997484240).

Almost surely, 2^{1645761355557} is an apocalyptic number.

It is an amenable number.

1645761355557 is a deficient number, since it is larger than the sum of its proper divisors (766208455323).

1645761355557 is a wasteful number, since it uses less digits than its factorization.

1645761355557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4533777864 (or 4533777853 counting only the distinct ones).

The product of its digits is 66150000, while the sum is 60.

The spelling of 1645761355557 in words is "one trillion, six hundred forty-five billion, seven hundred sixty-one million, three hundred fifty-five thousand, five hundred fifty-seven".