21350571 has 16 divisors (see below), whose sum is σ = 31317888. Its totient is φ = 12937320.

The previous prime is 21350551. The next prime is 21350597. The reversal of 21350571 is 17505312.

It is not a de Polignac number, because 21350571 - 2¹³ = 21342379 is a prime.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21350501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1320 + ... + 6666.

It is an arithmetic number, because the mean of its divisors is an integer number (1957368).

Almost surely, 2^21350571 is an apocalyptic number.

21350571 is a deficient number, since it is larger than the sum of its proper divisors (9967317).

21350571 is an equidigital number, since it uses as much as digits as its factorization.

21350571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5383 (or 5361 counting only the distinct ones).

The product of its (nonzero) digits is 1050, while the sum is 24.

The square root of 21350571 is about 4620.6678088778. The cubic root of 21350571 is about 277.4191891956.

Adding to 21350571 its reverse (17505312), we get a palindrome (38855883).

The spelling of 21350571 in words is "twenty-one million, three hundred fifty thousand, five hundred seventy-one".