1645356543447 has 16 divisors (see below), whose sum is σ = 2309352210560. Its totient is φ = 1039136612832.

The previous prime is 1645356543431. The next prime is 1645356543533. The reversal of 1645356543447 is 7443456535461.

It is not a de Polignac number, because 1645356543447 - 2⁴ = 1645356543431 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645356543427) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1214493 + ... + 2183049.

It is an arithmetic number, because the mean of its divisors is an integer number (144334513160).

Almost surely, 2^{1645356543447} is an apocalyptic number.

1645356543447 is a deficient number, since it is larger than the sum of its proper divisors (663995667113).

1645356543447 is a wasteful number, since it uses less digits than its factorization.

1645356543447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 998382.

The product of its digits is 72576000, while the sum is 57.

The spelling of 1645356543447 in words is "one trillion, six hundred forty-five billion, three hundred fifty-six million, five hundred forty-three thousand, four hundred forty-seven".