21355451464611 has 32 divisors (see below), whose sum is σ = 31647635504640. Its totient is φ = 12701148992000.

The previous prime is 21355451464609. The next prime is 21355451464621. The reversal of 21355451464611 is 11646415455312.

It is a cyclic number.

It is not a de Polignac number, because 21355451464611 - 2¹ = 21355451464609 is a prime.

It is a super-2 number, since 2×21355451464611² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21355451464601) 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, 27974151 + ... + 28727408.

It is an arithmetic number, because the mean of its divisors is an integer number (988988609520).

Almost surely, 2^{21355451464611} is an apocalyptic number.

21355451464611 is a deficient number, since it is larger than the sum of its proper divisors (10292184040029).

21355451464611 is a wasteful number, since it uses less digits than its factorization.

21355451464611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56701787.

The product of its digits is 1728000, while the sum is 48.

The spelling of 21355451464611 in words is "twenty-one trillion, three hundred fifty-five billion, four hundred fifty-one million, four hundred sixty-four thousand, six hundred eleven".