21661465732434 has 192 divisors, whose sum is σ = 52379464790016. Its totient is φ = 6467993532000.

The previous prime is 21661465732433. The next prime is 21661465732483. The reversal of 21661465732434 is 43423756416612.

21661465732434 is a `hidden beast` number, since 2 + 1 + 6 + 6 + 1 + 46 + 573 + 24 + 3 + 4 = 666.

It is not an unprimeable number, because it can be changed into a prime (21661465732433) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5666089047 + ... + 5666092869.

It is an arithmetic number, because the mean of its divisors is an integer number (272809712448).

Almost surely, 2^{21661465732434} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21661465732434, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26189732395008).

21661465732434 is an abundant number, since it is smaller than the sum of its proper divisors (30717999057582).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21661465732434 is a wasteful number, since it uses less digits than its factorization.

21661465732434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7266 (or 7241 counting only the distinct ones).

The product of its digits is 17418240, while the sum is 54.

The spelling of 21661465732434 in words is "twenty-one trillion, six hundred sixty-one billion, four hundred sixty-five million, seven hundred thirty-two thousand, four hundred thirty-four".