21015007101 has 24 divisors (see below), whose sum is σ = 33119105760. Its totient is φ = 12734618400.

The previous prime is 21015007087. The next prime is 21015007121. The reversal of 21015007101 is 10170051012.

It is a happy number.

It is not a de Polignac number, because 21015007101 - 2⁶ = 21015007037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21015007121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1381306 + ... + 1396436.

It is an arithmetic number, because the mean of its divisors is an integer number (1379962740).

Almost surely, 2^21015007101 is an apocalyptic number.

It is an amenable number.

21015007101 is a deficient number, since it is larger than the sum of its proper divisors (12104098659).

21015007101 is a wasteful number, since it uses less digits than its factorization.

21015007101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29177 (or 29174 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 18.

Adding to 21015007101 its reverse (10170051012), we get a palindrome (31185058113).

The spelling of 21015007101 in words is "twenty-one billion, fifteen million, seven thousand, one hundred one".