645442055461 has 16 divisors (see below), whose sum is σ = 787950993024. Its totient is φ = 516084839424.

The previous prime is 645442055399. The next prime is 645442055507. The reversal of 645442055461 is 164550244546.

It is not a de Polignac number, because 645442055461 - 2¹⁹ = 645441531173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645442059461) 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, 23986035 + ... + 24012928.

It is an arithmetic number, because the mean of its divisors is an integer number (49246937064).

Almost surely, 2^645442055461 is an apocalyptic number.

It is an amenable number.

645442055461 is a deficient number, since it is larger than the sum of its proper divisors (142508937563).

645442055461 is a wasteful number, since it uses less digits than its factorization.

645442055461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47999100.

The product of its (nonzero) digits is 2304000, while the sum is 46.

The spelling of 645442055461 in words is "six hundred forty-five billion, four hundred forty-two million, fifty-five thousand, four hundred sixty-one".