645125403 has 16 divisors (see below), whose sum is σ = 932242976. Its totient is φ = 394467840.

The previous prime is 645125399. The next prime is 645125419. The reversal of 645125403 is 304521546.

It is not a de Polignac number, because 645125403 - 2² = 645125399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645125483) 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 15 ways as a sum of consecutive naturals, for example, 46558 + ... + 58803.

It is an arithmetic number, because the mean of its divisors is an integer number (58265186).

Almost surely, 2^645125403 is an apocalyptic number.

645125403 is a deficient number, since it is larger than the sum of its proper divisors (287117573).

645125403 is a wasteful number, since it uses less digits than its factorization.

645125403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105534.

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 645125403 is about 25399.3189475624. The cubic root of 645125403 is about 864.0682508349.

Adding to 645125403 its reverse (304521546), we get a palindrome (949646949).

The spelling of 645125403 in words is "six hundred forty-five million, one hundred twenty-five thousand, four hundred three".