21064605406043 has 4 divisors (see below), whose sum is σ = 21099654666888. Its totient is φ = 21029556145200.

The previous prime is 21064605405971. The next prime is 21064605406079. The reversal of 21064605406043 is 34060450646012.

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 21064605406043 - 2⁸ = 21064605405787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21064605406093) 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, 17524629521 + ... + 17524630722.

It is an arithmetic number, because the mean of its divisors is an integer number (5274913666722).

Almost surely, 2^{21064605406043} is an apocalyptic number.

21064605406043 is a deficient number, since it is larger than the sum of its proper divisors (35049260845).

21064605406043 is an equidigital number, since it uses as much as digits as its factorization.

21064605406043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35049260844.

The product of its (nonzero) digits is 414720, while the sum is 41.

The spelling of 21064605406043 in words is "twenty-one trillion, sixty-four billion, six hundred five million, four hundred six thousand, forty-three".