20421001042 has 8 divisors (see below), whose sum is σ = 32987770956. Its totient is φ = 9425077392.

The previous prime is 20421001037. The next prime is 20421001057. The reversal of 20421001042 is 24010012402.

It can be written as a sum of positive squares in 2 ways, for example, as 19926427921 + 494573121 = 141161^2 + 22239^2 .

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

It is an unprimeable number.

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, 392711533 + ... + 392711584.

Almost surely, 2^20421001042 is an apocalyptic number.

20421001042 is a deficient number, since it is larger than the sum of its proper divisors (12566769914).

20421001042 is a wasteful number, since it uses less digits than its factorization.

20421001042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 785423132.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20421001042 its reverse (24010012402), we get a palindrome (44431013444).

The spelling of 20421001042 in words is "twenty billion, four hundred twenty-one million, one thousand, forty-two".