21951850 has 24 divisors (see below), whose sum is σ = 41297580. Its totient is φ = 8680320.

The previous prime is 21951847. The next prime is 21951857. The reversal of 21951850 is 5815912.

It can be written as a sum of positive squares in 6 ways, for example, as 3038049 + 18913801 = 1743^2 + 4349^2 .

It is not an unprimeable number, because it can be changed into a prime (21951857) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1984 + ... + 6916.

Almost surely, 2^21951850 is an apocalyptic number.

21951850 is a deficient number, since it is larger than the sum of its proper divisors (19345730).

21951850 is a wasteful number, since it uses less digits than its factorization.

21951850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5034 (or 5029 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 31.

The square root of 21951850 is about 4685.2801410375. The cubic root of 21951850 is about 279.9993622434. Note that the first 3 decimals are identical.

It can be divided in two parts, 21951 and 850, that added together give a square (22801 = 151²).

The spelling of 21951850 in words is "twenty-one million, nine hundred fifty-one thousand, eight hundred fifty".