643221542546 has 16 divisors (see below), whose sum is σ = 1078216157088. Its totient is φ = 285242368800.

The previous prime is 643221542519. The next prime is 643221542573. The reversal of 643221542546 is 645245122346.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (643221542519) and next prime (643221542573).

It is a junction number, because it is equal to n+sod(n) for n = 643221542497 and 643221542506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 356552060 + ... + 356553863.

It is an arithmetic number, because the mean of its divisors is an integer number (67388509818).

Almost surely, 2^643221542546 is an apocalyptic number.

643221542546 is a deficient number, since it is larger than the sum of its proper divisors (434994614542).

643221542546 is a wasteful number, since it uses less digits than its factorization.

643221542546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713105977.

The product of its digits is 1382400, while the sum is 44.

The spelling of 643221542546 in words is "six hundred forty-three billion, two hundred twenty-one million, five hundred forty-two thousand, five hundred forty-six".