21001110021002 has 4 divisors (see below), whose sum is σ = 31501665031506. Its totient is φ = 10500555010500.

The previous prime is 21001110020971. The next prime is 21001110021043. The reversal of 21001110021002 is 20012001110012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20688406499401 + 312703521601 = 4548451^2 + 559199^2 .

It is a super-2 number, since 2×21001110021002² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5250277505249 + ... + 5250277505252.

Almost surely, 2^{21001110021002} is an apocalyptic number.

21001110021002 is a deficient number, since it is larger than the sum of its proper divisors (10500555010504).

21001110021002 is a wasteful number, since it uses less digits than its factorization.

21001110021002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10500555010503.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21001110021002 its reverse (20012001110012), we get a palindrome (41013111131014).

The spelling of 21001110021002 in words is "twenty-one trillion, one billion, one hundred ten million, twenty-one thousand, two".