21155003102 has 4 divisors (see below), whose sum is σ = 31732504656. Its totient is φ = 10577501550.

The previous prime is 21155003101. The next prime is 21155003119. The reversal of 21155003102 is 20130055112.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155003101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5288750774 + ... + 5288750777.

It is an arithmetic number, because the mean of its divisors is an integer number (7933126164).

Almost surely, 2^21155003102 is an apocalyptic number.

21155003102 is a deficient number, since it is larger than the sum of its proper divisors (10577501554).

21155003102 is a wasteful number, since it uses less digits than its factorization.

21155003102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10577501553.

The product of its (nonzero) digits is 300, while the sum is 20.

Adding to 21155003102 its reverse (20130055112), we get a palindrome (41285058214).

The spelling of 21155003102 in words is "twenty-one billion, one hundred fifty-five million, three thousand, one hundred two".