21121177102 has 4 divisors (see below), whose sum is σ = 31681765656. Its totient is φ = 10560588550.

The previous prime is 21121177097. The next prime is 21121177141. The reversal of 21121177102 is 20177112112.

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

It is a super-2 number, since 2×21121177102² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5280294274 + ... + 5280294277.

It is an arithmetic number, because the mean of its divisors is an integer number (7920441414).

Almost surely, 2^21121177102 is an apocalyptic number.

21121177102 is a deficient number, since it is larger than the sum of its proper divisors (10560588554).

21121177102 is a wasteful number, since it uses less digits than its factorization.

21121177102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10560588553.

The product of its (nonzero) digits is 392, while the sum is 25.

Adding to 21121177102 its reverse (20177112112), we get a palindrome (41298289214).

The spelling of 21121177102 in words is "twenty-one billion, one hundred twenty-one million, one hundred seventy-seven thousand, one hundred two".