21974620 has 12 divisors (see below), whose sum is σ = 46146744. Its totient is φ = 8789840.

The previous prime is 21974599. The next prime is 21974627. The reversal of 21974620 is 2647912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21974627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 549346 + ... + 549385.

It is an arithmetic number, because the mean of its divisors is an integer number (3845562).

Almost surely, 2^21974620 is an apocalyptic number.

21974620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21974620 is an abundant number, since it is smaller than the sum of its proper divisors (24172124).

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

21974620 is a wasteful number, since it uses less digits than its factorization.

21974620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098740 (or 1098738 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 21974620 is about 4687.7094619867. The cubic root of 21974620 is about 280.0961404549.

The spelling of 21974620 in words is "twenty-one million, nine hundred seventy-four thousand, six hundred twenty".