21013145126 has 4 divisors (see below), whose sum is σ = 31519717692. Its totient is φ = 10506572562.

The previous prime is 21013145081. The next prime is 21013145149. The reversal of 21013145126 is 62154131012.

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

It is a junction number, because it is equal to n+sod(n) for n = 21013145095 and 21013145104.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5253286280 + ... + 5253286283.

It is an arithmetic number, because the mean of its divisors is an integer number (7879929423).

Almost surely, 2^21013145126 is an apocalyptic number.

21013145126 is a deficient number, since it is larger than the sum of its proper divisors (10506572566).

21013145126 is a wasteful number, since it uses less digits than its factorization.

21013145126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10506572565.

The product of its (nonzero) digits is 1440, while the sum is 26.

Adding to 21013145126 its reverse (62154131012), we get a palindrome (83167276138).

The spelling of 21013145126 in words is "twenty-one billion, thirteen million, one hundred forty-five thousand, one hundred twenty-six".