21153120641 has 8 divisors (see below), whose sum is σ = 22297862400. Its totient is φ = 20011520880.

The previous prime is 21153120613. The next prime is 21153120647. The reversal of 21153120641 is 14602135112.

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

It is a cyclic number.

It is not a de Polignac number, because 21153120641 - 2¹⁴ = 21153104257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21153120641.

It is not an unprimeable number, because it can be changed into a prime (21153120647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 771665 + ... + 798606.

It is an arithmetic number, because the mean of its divisors is an integer number (2787232800).

Almost surely, 2^21153120641 is an apocalyptic number.

It is an amenable number.

21153120641 is a deficient number, since it is larger than the sum of its proper divisors (1144741759).

21153120641 is a wasteful number, since it uses less digits than its factorization.

21153120641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1570999.

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

Adding to 21153120641 its reverse (14602135112), we get a palindrome (35755255753).

The spelling of 21153120641 in words is "twenty-one billion, one hundred fifty-three million, one hundred twenty thousand, six hundred forty-one".