645553013 has 4 divisors (see below), whose sum is σ = 737774880. Its totient is φ = 553331148.

The previous prime is 645552991. The next prime is 645553033. The reversal of 645553013 is 310355546.

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-645553013 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 (645553033) 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, 46110923 + ... + 46110936.

It is an arithmetic number, because the mean of its divisors is an integer number (184443720).

Almost surely, 2^645553013 is an apocalyptic number.

It is an amenable number.

645553013 is a deficient number, since it is larger than the sum of its proper divisors (92221867).

645553013 is an equidigital number, since it uses as much as digits as its factorization.

645553013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92221866.

The product of its (nonzero) digits is 27000, while the sum is 32.

The square root of 645553013 is about 25407.7352985267. The cubic root of 645553013 is about 864.2591194720.

The spelling of 645553013 in words is "six hundred forty-five million, five hundred fifty-three thousand, thirteen".