21651452 has 12 divisors (see below), whose sum is σ = 38456040. Its totient is φ = 10664016.

The previous prime is 21651449. The next prime is 21651473. The reversal of 21651452 is 25415612.

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, 40127 + ... + 40662.

It is an arithmetic number, because the mean of its divisors is an integer number (3204670).

Almost surely, 2^21651452 is an apocalyptic number.

It is an amenable number.

21651452 is a deficient number, since it is larger than the sum of its proper divisors (16804588).

21651452 is a wasteful number, since it uses less digits than its factorization.

21651452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80860 (or 80858 counting only the distinct ones).

The product of its digits is 2400, while the sum is 26.

The square root of 21651452 is about 4653.1120768793. The cubic root of 21651452 is about 278.7162834001.

The spelling of 21651452 in words is "twenty-one million, six hundred fifty-one thousand, four hundred fifty-two".