21531113245 has 16 divisors (see below), whose sum is σ = 25896804480. Its totient is φ = 17185291200.

The previous prime is 21531113231. The next prime is 21531113267. The reversal of 21531113245 is 54231113512.

It is not a de Polignac number, because 21531113245 - 2⁷ = 21531113117 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7636446 + ... + 7639264.

It is an arithmetic number, because the mean of its divisors is an integer number (1618550280).

Almost surely, 2^21531113245 is an apocalyptic number.

It is an amenable number.

21531113245 is a deficient number, since it is larger than the sum of its proper divisors (4365691235).

21531113245 is a wasteful number, since it uses less digits than its factorization.

21531113245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5796.

The product of its digits is 3600, while the sum is 28.

Adding to 21531113245 its reverse (54231113512), we get a palindrome (75762226757).

The spelling of 21531113245 in words is "twenty-one billion, five hundred thirty-one million, one hundred thirteen thousand, two hundred forty-five".