21321001019 has 16 divisors (see below), whose sum is σ = 22160565504. Its totient is φ = 20498032800.

The previous prime is 21321001003. The next prime is 21321001021. The reversal of 21321001019 is 91010012312.

It is a cyclic number.

It is not a de Polignac number, because 21321001019 - 2⁴ = 21321001003 is a prime.

It is a super-2 number, since 2×21321001019² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21321031019) 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 15 ways as a sum of consecutive naturals, for example, 1957649 + ... + 1968509.

It is an arithmetic number, because the mean of its divisors is an integer number (1385035344).

Almost surely, 2^21321001019 is an apocalyptic number.

21321001019 is a deficient number, since it is larger than the sum of its proper divisors (839564485).

21321001019 is a wasteful number, since it uses less digits than its factorization.

21321001019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11618.

The product of its (nonzero) digits is 108, while the sum is 20.

The spelling of 21321001019 in words is "twenty-one billion, three hundred twenty-one million, one thousand, nineteen".