21202809602 has 16 divisors (see below), whose sum is σ = 34603796472. Its totient is φ = 9685025280.

The previous prime is 21202809599. The next prime is 21202809629. The reversal of 21202809602 is 20690820212.

It can be written as a sum of positive squares in 4 ways, for example, as 18354559441 + 2848250161 = 135479^2 + 53369^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4201049 + ... + 4206092.

Almost surely, 2^21202809602 is an apocalyptic number.

21202809602 is a deficient number, since it is larger than the sum of its proper divisors (13400986870).

21202809602 is a wasteful number, since it uses less digits than its factorization.

21202809602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8407253.

The product of its (nonzero) digits is 6912, while the sum is 32.

The spelling of 21202809602 in words is "twenty-one billion, two hundred two million, eight hundred nine thousand, six hundred two".