21010552102 has 4 divisors (see below), whose sum is σ = 31515828156. Its totient is φ = 10505276050.

The previous prime is 21010552039. The next prime is 21010552103. The reversal of 21010552102 is 20125501012.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21010552102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010552103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5252638024 + ... + 5252638027.

It is an arithmetic number, because the mean of its divisors is an integer number (7878957039).

Almost surely, 2^21010552102 is an apocalyptic number.

21010552102 is a deficient number, since it is larger than the sum of its proper divisors (10505276054).

21010552102 is a wasteful number, since it uses less digits than its factorization.

21010552102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10505276053.

The product of its (nonzero) digits is 200, while the sum is 19.

The spelling of 21010552102 in words is "twenty-one billion, ten million, five hundred fifty-two thousand, one hundred two".