21820150 has 48 divisors (see below), whose sum is σ = 44840880. Its totient is φ = 7833600.

The previous prime is 21820133. The next prime is 21820157. The reversal of 21820150 is 5102812.

It is a super-2 number, since 2×21820150² = 952237892045000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21820157) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53146 + ... + 53554.

It is an arithmetic number, because the mean of its divisors is an integer number (934185).

Almost surely, 2^21820150 is an apocalyptic number.

21820150 is an abundant number, since it is smaller than the sum of its proper divisors (23020730).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21820150 is a wasteful number, since it uses less digits than its factorization.

21820150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 524 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 21820150 is about 4671.2043414948. The cubic root of 21820150 is about 279.4382871570.

Adding to 21820150 its reverse (5102812), we get a palindrome (26922962).

The spelling of 21820150 in words is "twenty-one million, eight hundred twenty thousand, one hundred fifty".