21400532 has 12 divisors (see below), whose sum is σ = 37573536. Its totient is φ = 10665240.

The previous prime is 21400523. The next prime is 21400583. The reversal of 21400532 is 23500412.

It is a self number, because there is not a number n which added to its sum of digits gives 21400532.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7358 + ... + 9845.

It is an arithmetic number, because the mean of its divisors is an integer number (3131128).

Almost surely, 2^21400532 is an apocalyptic number.

It is an amenable number.

21400532 is a deficient number, since it is larger than the sum of its proper divisors (16173004).

21400532 is a wasteful number, since it uses less digits than its factorization.

21400532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17518 (or 17516 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 21400532 is about 4626.0709030450. The cubic root of 21400532 is about 277.6354104712.

Adding to 21400532 its reverse (23500412), we get a palindrome (44900944).

The spelling of 21400532 in words is "twenty-one million, four hundred thousand, five hundred thirty-two".