21242520623 has 16 divisors (see below), whose sum is σ = 22423654080. Its totient is φ = 20100960000.

The previous prime is 21242520617. The next prime is 21242520641. The reversal of 21242520623 is 32602524212.

It is a cyclic number.

It is not a de Polignac number, because 21242520623 - 2⁸ = 21242520367 is a prime.

It is a super-3 number, since 3×21242520623³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242520613) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 147998 + ... + 253748.

It is an arithmetic number, because the mean of its divisors is an integer number (1401478380).

Almost surely, 2^21242520623 is an apocalyptic number.

21242520623 is a deficient number, since it is larger than the sum of its proper divisors (1181133457).

21242520623 is a wasteful number, since it uses less digits than its factorization.

21242520623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105938.

The product of its (nonzero) digits is 11520, while the sum is 29.

The spelling of 21242520623 in words is "twenty-one billion, two hundred forty-two million, five hundred twenty thousand, six hundred twenty-three".