643473031 has 4 divisors (see below), whose sum is σ = 660864232. Its totient is φ = 626081832.

The previous prime is 643473029. The next prime is 643473037. The reversal of 643473031 is 130374346.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 130374346 = 2 ⋅65187173.

It is a cyclic number.

It is not a de Polignac number, because 643473031 - 2¹ = 643473029 is a prime.

It is a super-2 number, since 2×643473031² = 828115083248653922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643472984 and 643473002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643473037) 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, 8695545 + ... + 8695618.

It is an arithmetic number, because the mean of its divisors is an integer number (165216058).

Almost surely, 2^643473031 is an apocalyptic number.

643473031 is a deficient number, since it is larger than the sum of its proper divisors (17391201).

643473031 is a wasteful number, since it uses less digits than its factorization.

643473031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17391200.

The product of its (nonzero) digits is 18144, while the sum is 31.

The square root of 643473031 is about 25366.7702122284. The cubic root of 643473031 is about 863.3299019291.

The spelling of 643473031 in words is "six hundred forty-three million, four hundred seventy-three thousand, thirty-one".