645634345051 has 4 divisors (see below), whose sum is σ = 656218514704. Its totient is φ = 635050175400.

The previous prime is 645634345003. The next prime is 645634345093. The reversal of 645634345051 is 150543436546.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 645634345051 - 2¹³ = 645634336859 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645634344992 and 645634345010.

It is not an unprimeable number, because it can be changed into a prime (645634342051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5292084735 + ... + 5292084856.

It is an arithmetic number, because the mean of its divisors is an integer number (164054628676).

Almost surely, 2^645634345051 is an apocalyptic number.

645634345051 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

645634345051 is a deficient number, since it is larger than the sum of its proper divisors (10584169653).

645634345051 is a wasteful number, since it uses less digits than its factorization.

645634345051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10584169652.

The product of its (nonzero) digits is 2592000, while the sum is 46.

The spelling of 645634345051 in words is "six hundred forty-five billion, six hundred thirty-four million, three hundred forty-five thousand, fifty-one".