21500346220157 has 8 divisors (see below), whose sum is σ = 24572050267200. Its totient is φ = 18428698677024.

The previous prime is 21500346220153. The next prime is 21500346220163. The reversal of 21500346220157 is 75102264300512.

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

It is a cyclic number.

It is not a de Polignac number, because 21500346220157 - 2² = 21500346220153 is a prime.

It is a super-2 number, since 2×21500346220157² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21500346220157.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21500346220153) 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, 13307432 + ... + 14835377.

It is an arithmetic number, because the mean of its divisors is an integer number (3071506283400).

Almost surely, 2^{21500346220157} is an apocalyptic number.

It is an amenable number.

21500346220157 is a deficient number, since it is larger than the sum of its proper divisors (3071704047043).

21500346220157 is a wasteful number, since it uses less digits than its factorization.

21500346220157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28251955.

The product of its (nonzero) digits is 100800, while the sum is 38.

The spelling of 21500346220157 in words is "twenty-one trillion, five hundred billion, three hundred forty-six million, two hundred twenty thousand, one hundred fifty-seven".