643245362426 has 4 divisors (see below), whose sum is σ = 964868043642. Its totient is φ = 321622681212.

The previous prime is 643245362413. The next prime is 643245362437. The reversal of 643245362426 is 624263542346.

643245362426 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 624263542346 = 2 ⋅312131771173.

It can be written as a sum of positive squares in only one way, i.e., 530952682225 + 112292680201 = 728665^2 + 335101^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160811340605 + ... + 160811340608.

Almost surely, 2^643245362426 is an apocalyptic number.

643245362426 is a deficient number, since it is larger than the sum of its proper divisors (321622681216).

643245362426 is a wasteful number, since it uses less digits than its factorization.

643245362426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321622681215.

The product of its digits is 4976640, while the sum is 47.

The spelling of 643245362426 in words is "six hundred forty-three billion, two hundred forty-five million, three hundred sixty-two thousand, four hundred twenty-six".