21488550 has 24 divisors (see below), whose sum is σ = 53291976. Its totient is φ = 5730240.

The previous prime is 21488543. The next prime is 21488557. The reversal of 21488550 is 5588412.

It is an interprime number because it is at equal distance from previous prime (21488543) and next prime (21488557).

It is a super-2 number, since 2×21488550² = 923515562205000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21488557) 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, 71479 + ... + 71778.

It is an arithmetic number, because the mean of its divisors is an integer number (2220499).

Almost surely, 2^21488550 is an apocalyptic number.

21488550 is an abundant number, since it is smaller than the sum of its proper divisors (31803426).

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

21488550 is a wasteful number, since it uses less digits than its factorization.

21488550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143272 (or 143267 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 33.

The square root of 21488550 is about 4635.5743980655. The cubic root of 21488550 is about 278.0155176542.

The spelling of 21488550 in words is "twenty-one million, four hundred eighty-eight thousand, five hundred fifty".