21217047540837 has 8 divisors (see below), whose sum is σ = 28291430960736. Its totient is φ = 14143681240752.

The previous prime is 21217047540823. The next prime is 21217047540883. The reversal of 21217047540837 is 73804574071212.

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

It is not a de Polignac number, because 21217047540837 - 2⁷ = 21217047540709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21217047540837.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21217047540737) 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, 254231278 + ... + 254314719.

It is an arithmetic number, because the mean of its divisors is an integer number (3536428870092).

Almost surely, 2^{21217047540837} is an apocalyptic number.

It is an amenable number.

21217047540837 is a deficient number, since it is larger than the sum of its proper divisors (7074383419899).

21217047540837 is a wasteful number, since it uses less digits than its factorization.

21217047540837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508559907.

The product of its (nonzero) digits is 2634240, while the sum is 51.

The spelling of 21217047540837 in words is "twenty-one trillion, two hundred seventeen billion, forty-seven million, five hundred forty thousand, eight hundred thirty-seven".