643621432142 has 32 divisors (see below), whose sum is σ = 1129720811520. Its totient is φ = 272343396960.

The previous prime is 643621432087. The next prime is 643621432177. The reversal of 643621432142 is 241234126346.

It is a super-2 number, since 2×643621432142² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 643621432096 and 643621432105.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20998838 + ... + 21029465.

It is an arithmetic number, because the mean of its divisors is an integer number (35303775360).

Almost surely, 2^643621432142 is an apocalyptic number.

643621432142 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

643621432142 is a deficient number, since it is larger than the sum of its proper divisors (486099379378).

643621432142 is a wasteful number, since it uses less digits than its factorization.

643621432142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42028368.

The product of its digits is 165888, while the sum is 38.

Adding to 643621432142 its reverse (241234126346), we get a palindrome (884855558488).

The spelling of 643621432142 in words is "six hundred forty-three billion, six hundred twenty-one million, four hundred thirty-two thousand, one hundred forty-two".