21409519642 has 128 divisors (see below), whose sum is σ = 40052413440. Its totient is φ = 8389785600.

The previous prime is 21409519633. The next prime is 21409519657. The reversal of 21409519642 is 24691590412.

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 63 ways as a sum of consecutive naturals, for example, 156273798 + ... + 156273934.

It is an arithmetic number, because the mean of its divisors is an integer number (312909480).

Almost surely, 2^21409519642 is an apocalyptic number.

21409519642 is a deficient number, since it is larger than the sum of its proper divisors (18642893798).

21409519642 is a wasteful number, since it uses less digits than its factorization.

21409519642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416.

The product of its (nonzero) digits is 155520, while the sum is 43.

The spelling of 21409519642 in words is "twenty-one billion, four hundred nine million, five hundred nineteen thousand, six hundred forty-two".