645031093 has 4 divisors (see below), whose sum is σ = 737178400. Its totient is φ = 552883788.

The previous prime is 645031087. The next prime is 645031099. The reversal of 645031093 is 390130546.

645031093 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 an interprime number because it is at equal distance from previous prime (645031087) and next prime (645031099).

It is a cyclic number.

It is not a de Polignac number, because 645031093 - 2⁵ = 645031061 is a prime.

It is a super-2 number, since 2×645031093² = 832130221873549298, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645031099) 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, 46073643 + ... + 46073656.

It is an arithmetic number, because the mean of its divisors is an integer number (184294600).

Almost surely, 2^645031093 is an apocalyptic number.

It is an amenable number.

645031093 is a deficient number, since it is larger than the sum of its proper divisors (92147307).

645031093 is an equidigital number, since it uses as much as digits as its factorization.

645031093 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92147306.

The product of its (nonzero) digits is 9720, while the sum is 31.

The square root of 645031093 is about 25397.4623338632. The cubic root of 645031093 is about 864.0261431311.

The spelling of 645031093 in words is "six hundred forty-five million, thirty-one thousand, ninety-three".