21402179810002 has 4 divisors (see below), whose sum is σ = 32103269715006. Its totient is φ = 10701089905000.

The previous prime is 21402179809949. The next prime is 21402179810021. The reversal of 21402179810002 is 20001897120412.

It is a Cunningham number, because it is equal to 4626249²+1.

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., 21402179810001 + 1 = 4626249^2 + 1^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5350544952499 + ... + 5350544952502.

Almost surely, 2^{21402179810002} is an apocalyptic number.

21402179810002 is a deficient number, since it is larger than the sum of its proper divisors (10701089905004).

21402179810002 is a wasteful number, since it uses less digits than its factorization.

21402179810002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10701089905003.

The product of its (nonzero) digits is 16128, while the sum is 37.

The spelling of 21402179810002 in words is "twenty-one trillion, four hundred two billion, one hundred seventy-nine million, eight hundred ten thousand, two".