21572350 has 12 divisors (see below), whose sum is σ = 40124664. Its totient is φ = 8628920.

The previous prime is 21572339. The next prime is 21572359. The reversal of 21572350 is 5327512.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21572359) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215674 + ... + 215773.

It is an arithmetic number, because the mean of its divisors is an integer number (3343722).

Almost surely, 2^21572350 is an apocalyptic number.

21572350 is a deficient number, since it is larger than the sum of its proper divisors (18552314).

21572350 is a wasteful number, since it uses less digits than its factorization.

21572350 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431459 (or 431454 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 21572350 is about 4644.6043965014. The cubic root of 21572350 is about 278.3764460051.

Adding to 21572350 its reverse (5327512), we get a palindrome (26899862).

The spelling of 21572350 in words is "twenty-one million, five hundred seventy-two thousand, three hundred fifty".