21013641526 has 4 divisors (see below), whose sum is σ = 31520462292. Its totient is φ = 10506820762.

The previous prime is 21013641479. The next prime is 21013641529. The reversal of 21013641526 is 62514631012.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013641529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5253410380 + ... + 5253410383.

It is an arithmetic number, because the mean of its divisors is an integer number (7880115573).

Almost surely, 2^21013641526 is an apocalyptic number.

21013641526 is a deficient number, since it is larger than the sum of its proper divisors (10506820766).

21013641526 is a wasteful number, since it uses less digits than its factorization.

21013641526 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10506820765.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 21013641526 in words is "twenty-one billion, thirteen million, six hundred forty-one thousand, five hundred twenty-six".