21253363665401 has 8 divisors (see below), whose sum is σ = 24450416479104. Its totient is φ = 18096525352800.

The previous prime is 21253363665353. The next prime is 21253363665409. The reversal of 21253363665401 is 10456636335212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21253363665401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21253363665409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10053624140 + ... + 10053626253.

It is an arithmetic number, because the mean of its divisors is an integer number (3056302059888).

Almost surely, 2^{21253363665401} is an apocalyptic number.

It is an amenable number.

21253363665401 is a deficient number, since it is larger than the sum of its proper divisors (3197052813703).

21253363665401 is a wasteful number, since it uses less digits than its factorization.

21253363665401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20107250551.

The product of its (nonzero) digits is 2332800, while the sum is 47.

The spelling of 21253363665401 in words is "twenty-one trillion, two hundred fifty-three billion, three hundred sixty-three million, six hundred sixty-five thousand, four hundred one".