21121002010 has 8 divisors (see below), whose sum is σ = 38017803636. Its totient is φ = 8448400800.

The previous prime is 21121001969. The next prime is 21121002029. The reversal of 21121002010 is 1020012112.

It can be written as a sum of positive squares in 2 ways, for example, as 19595240289 + 1525761721 = 139983^2 + 39061^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (10), and also a Moran number because the ratio is a prime number: 2112100201 = 21121002010 / (2 + 1 + 1 + 2 + 1 + 0 + 0 + 2 + 0 + 1 + 0).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1056050091 + ... + 1056050110.

Almost surely, 2^21121002010 is an apocalyptic number.

21121002010 is a deficient number, since it is larger than the sum of its proper divisors (16896801626).

21121002010 is a wasteful number, since it uses less digits than its factorization.

21121002010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2112100208.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21121002010 its reverse (1020012112), we get a palindrome (22141014122).

The spelling of 21121002010 in words is "twenty-one billion, one hundred twenty-one million, two thousand, ten".