21019902002 has 32 divisors (see below), whose sum is σ = 34641838080. Its totient is φ = 9486389520.

The previous prime is 21019901993. The next prime is 21019902031. The reversal of 21019902002 is 20020991012.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4584203 + ... + 4588785.

It is an arithmetic number, because the mean of its divisors is an integer number (1082557440).

Almost surely, 2^21019902002 is an apocalyptic number.

21019902002 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21019902002 is a deficient number, since it is larger than the sum of its proper divisors (13621936078).

21019902002 is a wasteful number, since it uses less digits than its factorization.

21019902002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6038.

The product of its (nonzero) digits is 648, while the sum is 26.

The spelling of 21019902002 in words is "twenty-one billion, nineteen million, nine hundred two thousand, two".