21434532666 has 16 divisors (see below), whose sum is σ = 43508902944. Its totient is φ = 7038204624.

The previous prime is 21434532661. The next prime is 21434532673. The reversal of 21434532666 is 66623543412.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21434532661) 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, 26659465 + ... + 26660268.

It is an arithmetic number, because the mean of its divisors is an integer number (2719306434).

Almost surely, 2^21434532666 is an apocalyptic number.

21434532666 is an abundant number, since it is smaller than the sum of its proper divisors (22074370278).

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

21434532666 is a wasteful number, since it uses less digits than its factorization.

21434532666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53319805.

The product of its digits is 622080, while the sum is 42.

The spelling of 21434532666 in words is "twenty-one billion, four hundred thirty-four million, five hundred thirty-two thousand, six hundred sixty-six".