21925740 has 48 divisors (see below), whose sum is σ = 63514080. Its totient is φ = 5644800.

The previous prime is 21925697. The next prime is 21925741. The reversal of 21925740 is 4752912.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21925698 and 21925707.

It is not an unprimeable number, because it can be changed into a prime (21925741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4561 + ... + 8040.

It is an arithmetic number, because the mean of its divisors is an integer number (1323210).

Almost surely, 2^21925740 is an apocalyptic number.

21925740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21925740 is an abundant number, since it is smaller than the sum of its proper divisors (41588340).

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

21925740 is a wasteful number, since it uses less digits than its factorization.

21925740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12642 (or 12640 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 21925740 is about 4682.4929257822. The cubic root of 21925740 is about 279.8883057904. Note that the first 3 decimals are identical.

The spelling of 21925740 in words is "twenty-one million, nine hundred twenty-five thousand, seven hundred forty".