21019020442 has 48 divisors (see below), whose sum is σ = 37712122560. Its totient is φ = 8606258496.

The previous prime is 21019020437. The next prime is 21019020497. The reversal of 21019020442 is 24402091012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11989438 + ... + 11991190.

It is an arithmetic number, because the mean of its divisors is an integer number (785669220).

Almost surely, 2^21019020442 is an apocalyptic number.

21019020442 is a deficient number, since it is larger than the sum of its proper divisors (16693102118).

21019020442 is a wasteful number, since it uses less digits than its factorization.

21019020442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3427 (or 3404 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The spelling of 21019020442 in words is "twenty-one billion, nineteen million, twenty thousand, four hundred forty-two".