21042111042002 has 4 divisors (see below), whose sum is σ = 31563166563006. Its totient is φ = 10521055521000.

The previous prime is 21042111041951. The next prime is 21042111042047. The reversal of 21042111042002 is 20024011124012.

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., 19386593926441 + 1655517115561 = 4403021^2 + 1286669^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5260527760499 + ... + 5260527760502.

Almost surely, 2^{21042111042002} is an apocalyptic number.

21042111042002 is a deficient number, since it is larger than the sum of its proper divisors (10521055521004).

21042111042002 is a wasteful number, since it uses less digits than its factorization.

21042111042002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10521055521003.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21042111042002 its reverse (20024011124012), we get a palindrome (41066122166014).

The spelling of 21042111042002 in words is "twenty-one trillion, forty-two billion, one hundred eleven million, forty-two thousand, two".