21243076957501 has 32 divisors (see below), whose sum is σ = 24669221068800. Its totient is φ = 17917474829760.

The previous prime is 21243076957493. The next prime is 21243076957507. The reversal of 21243076957501 is 10575967034212.

It is a cyclic number.

It is not a de Polignac number, because 21243076957501 - 2³ = 21243076957493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243076957507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71143446 + ... + 71441416.

It is an arithmetic number, because the mean of its divisors is an integer number (770913158400).

Almost surely, 2^{21243076957501} is an apocalyptic number.

It is an amenable number.

21243076957501 is a deficient number, since it is larger than the sum of its proper divisors (3426144111299).

21243076957501 is a wasteful number, since it uses less digits than its factorization.

21243076957501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298729.

The product of its (nonzero) digits is 3175200, while the sum is 52.

The spelling of 21243076957501 in words is "twenty-one trillion, two hundred forty-three billion, seventy-six million, nine hundred fifty-seven thousand, five hundred one".