645724440419 has 8 divisors (see below), whose sum is σ = 657461094000. Its totient is φ = 634014192672.

The previous prime is 645724440409. The next prime is 645724440437. The reversal of 645724440419 is 914044427546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645724440419 is a prime.

It is a super-2 number, since 2×645724440419² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645724440409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6552104 + ... + 6649925.

It is an arithmetic number, because the mean of its divisors is an integer number (82182636750).

Almost surely, 2^645724440419 is an apocalyptic number.

645724440419 is a deficient number, since it is larger than the sum of its proper divisors (11736653581).

645724440419 is a wasteful number, since it uses less digits than its factorization.

645724440419 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13202917.

The product of its (nonzero) digits is 3870720, while the sum is 50.

The spelling of 645724440419 in words is "six hundred forty-five billion, seven hundred twenty-four million, four hundred forty thousand, four hundred nineteen".