21123375446 has 4 divisors (see below), whose sum is σ = 31685063172. Its totient is φ = 10561687722.

The previous prime is 21123375437. The next prime is 21123375491. The reversal of 21123375446 is 64457332112.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5280843860 + ... + 5280843863.

It is an arithmetic number, because the mean of its divisors is an integer number (7921265793).

Almost surely, 2^21123375446 is an apocalyptic number.

21123375446 is a deficient number, since it is larger than the sum of its proper divisors (10561687726).

21123375446 is a wasteful number, since it uses less digits than its factorization.

21123375446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10561687725.

The product of its digits is 120960, while the sum is 38.

The spelling of 21123375446 in words is "twenty-one billion, one hundred twenty-three million, three hundred seventy-five thousand, four hundred forty-six".