21126532317 has 8 divisors (see below), whose sum is σ = 30729501600. Its totient is φ = 12803958960.

The previous prime is 21126532279. The next prime is 21126532337. The reversal of 21126532317 is 71323562112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21126532317 - 2¹² = 21126528221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 640197949 = 21126532317 / (2 + 1 + 1 + 2 + 6 + 5 + 3 + 2 + 3 + 1 + 7).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126532337) 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, 320098942 + ... + 320099007.

It is an arithmetic number, because the mean of its divisors is an integer number (3841187700).

Almost surely, 2^21126532317 is an apocalyptic number.

It is an amenable number.

21126532317 is a deficient number, since it is larger than the sum of its proper divisors (9602969283).

21126532317 is a wasteful number, since it uses less digits than its factorization.

21126532317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640197963.

The product of its digits is 15120, while the sum is 33.

The spelling of 21126532317 in words is "twenty-one billion, one hundred twenty-six million, five hundred thirty-two thousand, three hundred seventeen".