21532433257 has 16 divisors (see below), whose sum is σ = 22914385920. Its totient is φ = 20163451392.

The previous prime is 21532433243. The next prime is 21532433261. The reversal of 21532433257 is 75233423512.

It is not a de Polignac number, because 21532433257 - 2¹⁵ = 21532400489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21532433207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8705773 + ... + 8708245.

It is an arithmetic number, because the mean of its divisors is an integer number (1432149120).

Almost surely, 2^21532433257 is an apocalyptic number.

It is an amenable number.

21532433257 is a deficient number, since it is larger than the sum of its proper divisors (1381952663).

21532433257 is a wasteful number, since it uses less digits than its factorization.

21532433257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4872.

The product of its digits is 151200, while the sum is 37.

Adding to 21532433257 its reverse (75233423512), we get a palindrome (96765856769).

The spelling of 21532433257 in words is "twenty-one billion, five hundred thirty-two million, four hundred thirty-three thousand, two hundred fifty-seven".