645556054 has 48 divisors (see below), whose sum is σ = 1154425104. Its totient is φ = 268931520.

The previous prime is 645556039. The next prime is 645556061. The reversal of 645556054 is 450655546.

It is a junction number, because it is equal to n+sod(n) for n = 645555998 and 645556016.

It is a congruent number.

It is an unprimeable number.

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, 493269 + ... + 494575.

It is an arithmetic number, because the mean of its divisors is an integer number (24050523).

Almost surely, 2^645556054 is an apocalyptic number.

645556054 is a deficient number, since it is larger than the sum of its proper divisors (508869050).

645556054 is a wasteful number, since it uses less digits than its factorization.

645556054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1501 (or 1490 counting only the distinct ones).

The product of its (nonzero) digits is 360000, while the sum is 40.

The square root of 645556054 is about 25407.7951424361. The cubic root of 645556054 is about 864.2604765555.

The spelling of 645556054 in words is "six hundred forty-five million, five hundred fifty-six thousand, fifty-four".