21230437994 has 8 divisors (see below), whose sum is σ = 31849326468. Its totient is φ = 10613995840.

The previous prime is 21230437979. The next prime is 21230437997. The reversal of 21230437994 is 49973403212.

It can be written as a sum of positive squares in 2 ways, for example, as 21224701969 + 5736025 = 145687^2 + 2395^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21230437997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 589727 + ... + 624690.

Almost surely, 2^21230437994 is an apocalyptic number.

21230437994 is a deficient number, since it is larger than the sum of its proper divisors (10618888474).

21230437994 is a wasteful number, since it uses less digits than its factorization.

21230437994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223160.

The product of its (nonzero) digits is 326592, while the sum is 44.

The spelling of 21230437994 in words is "twenty-one billion, two hundred thirty million, four hundred thirty-seven thousand, nine hundred ninety-four".