21512554442 has 32 divisors (see below), whose sum is σ = 33879057408. Its totient is φ = 10225454976.

The previous prime is 21512554387. The next prime is 21512554487. The reversal of 21512554442 is 24445521512.

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 15 ways as a sum of consecutive naturals, for example, 7928078 + ... + 7930790.

It is an arithmetic number, because the mean of its divisors is an integer number (1058720544).

Almost surely, 2^21512554442 is an apocalyptic number.

21512554442 is a deficient number, since it is larger than the sum of its proper divisors (12366502966).

21512554442 is a wasteful number, since it uses less digits than its factorization.

21512554442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3734.

The product of its digits is 64000, while the sum is 35.

The spelling of 21512554442 in words is "twenty-one billion, five hundred twelve million, five hundred fifty-four thousand, four hundred forty-two".