21498529 has 8 divisors (see below), whose sum is σ = 23201640. Its totient is φ = 19802496.

The previous prime is 21498511. The next prime is 21498539. The reversal of 21498529 is 92589412.

It can be written as a sum of positive squares in 4 ways, for example, as 3240000 + 18258529 = 1800^2 + 4273^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21498529 - 2¹⁵ = 21465761 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21498491 and 21498500.

It is not an unprimeable number, because it can be changed into a prime (21498539) 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, 5757 + ... + 8725.

It is an arithmetic number, because the mean of its divisors is an integer number (2900205).

Almost surely, 2^21498529 is an apocalyptic number.

It is an amenable number.

21498529 is a deficient number, since it is larger than the sum of its proper divisors (1703111).

21498529 is a wasteful number, since it uses less digits than its factorization.

21498529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3539.

The product of its digits is 51840, while the sum is 40.

The square root of 21498529 is about 4636.6506230252. The cubic root of 21498529 is about 278.0585465775.

The spelling of 21498529 in words is "twenty-one million, four hundred ninety-eight thousand, five hundred twenty-nine".