643251203 has 4 divisors (see below), whose sum is σ = 735144240. Its totient is φ = 551358168.

The previous prime is 643251187. The next prime is 643251221. The reversal of 643251203 is 302152346.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 302152346 = 2 ⋅151076173.

It is a cyclic number.

It is not a de Polignac number, because 643251203 - 2⁴ = 643251187 is a prime.

It is a super-2 number, since 2×643251203² = 827544220321894418, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643251503) 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, 45946508 + ... + 45946521.

It is an arithmetic number, because the mean of its divisors is an integer number (183786060).

Almost surely, 2^643251203 is an apocalyptic number.

643251203 is a deficient number, since it is larger than the sum of its proper divisors (91893037).

643251203 is an equidigital number, since it uses as much as digits as its factorization.

643251203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91893036.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 643251203 is about 25362.3974221681. The cubic root of 643251203 is about 863.2306837038.

The spelling of 643251203 in words is "six hundred forty-three million, two hundred fifty-one thousand, two hundred three".