643151099 has 4 divisors (see below), whose sum is σ = 644211264. Its totient is φ = 642090936.

The previous prime is 643151071. The next prime is 643151111. The reversal of 643151099 is 990151346.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 643151099 - 2¹⁶ = 643085563 is a prime.

It is a super-2 number, since 2×643151099² = 827286672289815602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643151029) 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, 529172 + ... + 530385.

It is an arithmetic number, because the mean of its divisors is an integer number (161052816).

Almost surely, 2^643151099 is an apocalyptic number.

643151099 is a deficient number, since it is larger than the sum of its proper divisors (1060165).

643151099 is a wasteful number, since it uses less digits than its factorization.

643151099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060164.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 643151099 is about 25360.4238726406. The cubic root of 643151099 is about 863.1859021695.

The spelling of 643151099 in words is "six hundred forty-three million, one hundred fifty-one thousand, ninety-nine".