645168741 has 24 divisors (see below), whose sum is σ = 1027723680. Its totient is φ = 358700832.

The previous prime is 645168707. The next prime is 645168749. The reversal of 645168741 is 147861546.

It is not a de Polignac number, because 645168741 - 2⁶ = 645168677 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 645168693 and 645168702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645168749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53871 + ... + 64748.

It is an arithmetic number, because the mean of its divisors is an integer number (42821820).

Almost surely, 2^645168741 is an apocalyptic number.

It is an amenable number.

645168741 is a deficient number, since it is larger than the sum of its proper divisors (382554939).

645168741 is a wasteful number, since it uses less digits than its factorization.

645168741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118673 (or 118666 counting only the distinct ones).

The product of its digits is 161280, while the sum is 42.

The square root of 645168741 is about 25400.1720663463. The cubic root of 645168741 is about 864.0875990893.

The spelling of 645168741 in words is "six hundred forty-five million, one hundred sixty-eight thousand, seven hundred forty-one".