21532312 has 32 divisors (see below), whose sum is σ = 41368320. Its totient is φ = 10504480.

The previous prime is 21532309. The next prime is 21532327. The reversal of 21532312 is 21323512.

It is a self number, because there is not a number n which added to its sum of digits gives 21532312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94743 + ... + 94969.

It is an arithmetic number, because the mean of its divisors is an integer number (1292760).

Almost surely, 2^21532312 is an apocalyptic number.

It is an amenable number.

21532312 is a deficient number, since it is larger than the sum of its proper divisors (19836008).

21532312 is a wasteful number, since it uses less digits than its factorization.

21532312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471 (or 467 counting only the distinct ones).

The product of its digits is 360, while the sum is 19.

The square root of 21532312 is about 4640.2922321768. The cubic root of 21532312 is about 278.2041183318.

Adding to 21532312 its reverse (21323512), we get a palindrome (42855824).

It can be divided in two parts, 2153 and 2312, that added together give a triangular number (4465 = T₉₄).

The spelling of 21532312 in words is "twenty-one million, five hundred thirty-two thousand, three hundred twelve".