645015403 has 8 divisors (see below), whose sum is σ = 671582016. Its totient is φ = 618964800.

The previous prime is 645015383. The next prime is 645015431. The reversal of 645015403 is 304510546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645015403 - 2¹³ = 645007211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645045403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126451 + ... + 131452.

It is an arithmetic number, because the mean of its divisors is an integer number (83947752).

Almost surely, 2^645015403 is an apocalyptic number.

645015403 is a deficient number, since it is larger than the sum of its proper divisors (26566613).

645015403 is a wasteful number, since it uses less digits than its factorization.

645015403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258005.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 645015403 is about 25397.1534428565. The cubic root of 645015403 is about 864.0191374326.

Adding to 645015403 its reverse (304510546), we get a palindrome (949525949).

The spelling of 645015403 in words is "six hundred forty-five million, fifteen thousand, four hundred three".