645019629 has 4 divisors (see below), whose sum is σ = 860026176. Its totient is φ = 430013084.

The previous prime is 645019621. The next prime is 645019679. The reversal of 645019629 is 926910546.

It is a happy number.

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 not a de Polignac number, because 645019629 - 2³ = 645019621 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645019621) 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, 107503269 + ... + 107503274.

It is an arithmetic number, because the mean of its divisors is an integer number (215006544).

Almost surely, 2^645019629 is an apocalyptic number.

It is an amenable number.

645019629 is a deficient number, since it is larger than the sum of its proper divisors (215006547).

645019629 is a wasteful number, since it uses less digits than its factorization.

645019629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215006546.

The product of its (nonzero) digits is 116640, while the sum is 42.

The square root of 645019629 is about 25397.2366410206. The cubic root of 645019629 is about 864.0210243834.

The spelling of 645019629 in words is "six hundred forty-five million, nineteen thousand, six hundred twenty-nine".