645646342469 has 4 divisors (see below), whose sum is σ = 651680420544. Its totient is φ = 639612264396.

The previous prime is 645646342463. The next prime is 645646342499. The reversal of 645646342469 is 964243646546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645646342469 is a prime.

It is a super-2 number, since 2×645646342469² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645646342463) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3017038877 + ... + 3017039090.

It is an arithmetic number, because the mean of its divisors is an integer number (162920105136).

Almost surely, 2^645646342469 is an apocalyptic number.

It is an amenable number.

645646342469 is a deficient number, since it is larger than the sum of its proper divisors (6034078075).

645646342469 is a wasteful number, since it uses less digits than its factorization.

645646342469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6034078074.

The product of its digits is 89579520, while the sum is 59.

The spelling of 645646342469 in words is "six hundred forty-five billion, six hundred forty-six million, three hundred forty-two thousand, four hundred sixty-nine".