21741630 has 16 divisors (see below), whose sum is σ = 52179984. Its totient is φ = 5797760.

The previous prime is 21741613. The next prime is 21741631. The reversal of 21741630 is 3614712.

It is a self number, because there is not a number n which added to its sum of digits gives 21741630.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21741631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 362331 + ... + 362390.

It is an arithmetic number, because the mean of its divisors is an integer number (3261249).

Almost surely, 2^21741630 is an apocalyptic number.

21741630 is an abundant number, since it is smaller than the sum of its proper divisors (30438354).

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

21741630 is a wasteful number, since it uses less digits than its factorization.

21741630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724731.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 21741630 is about 4662.7920820041. The cubic root of 21741630 is about 279.1026972560.

The spelling of 21741630 in words is "twenty-one million, seven hundred forty-one thousand, six hundred thirty".