21940030 has 64 divisors (see below), whose sum is σ = 48522240. Its totient is φ = 6971904.

The previous prime is 21940027. The next prime is 21940063. The reversal of 21940030 is 3004912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 122481 + ... + 122659.

It is an arithmetic number, because the mean of its divisors is an integer number (758160).

Almost surely, 2^21940030 is an apocalyptic number.

21940030 is an abundant number, since it is smaller than the sum of its proper divisors (26582210).

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

21940030 is a wasteful number, since it uses less digits than its factorization.

21940030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 21940030 is about 4684.0185738317. The cubic root of 21940030 is about 279.9490978898.

Adding to 21940030 its reverse (3004912), we get a palindrome (24944942).

The spelling of 21940030 in words is "twenty-one million, nine hundred forty thousand, thirty".