21601672645051 has 8 divisors (see below), whose sum is σ = 21972914398800. Its totient is φ = 21231867030528.

The previous prime is 21601672645037. The next prime is 21601672645079. The reversal of 21601672645051 is 15054627610612.

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-21601672645051 is a prime.

It is a super-2 number, since 2×21601672645051² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21601672644992 and 21601672645010.

It is not an unprimeable number, because it can be changed into a prime (21601672645001) 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, 359004466 + ... + 359064631.

It is an arithmetic number, because the mean of its divisors is an integer number (2746614299850).

Almost surely, 2^{21601672645051} is an apocalyptic number.

21601672645051 is a deficient number, since it is larger than the sum of its proper divisors (371241753749).

21601672645051 is an equidigital number, since it uses as much as digits as its factorization.

21601672645051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 718069613.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 21601672645051 in words is "twenty-one trillion, six hundred one billion, six hundred seventy-two million, six hundred forty-five thousand, fifty-one".