21452031 has 24 divisors (see below), whose sum is σ = 33386496. Its totient is φ = 13234320.

The previous prime is 21452029. The next prime is 21452051. The reversal of 21452031 is 13025412.

It is not a de Polignac number, because 21452031 - 2¹ = 21452029 is a prime.

It is a super-2 number, since 2×21452031² = 920379268049922, which contains 22 as substring.

It is a plaindrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 21451995 and 21452013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21452021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4746 + ... + 8088.

It is an arithmetic number, because the mean of its divisors is an integer number (1391104).

Almost surely, 2^21452031 is an apocalyptic number.

21452031 is a deficient number, since it is larger than the sum of its proper divisors (11934465).

21452031 is a wasteful number, since it uses less digits than its factorization.

21452031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3403 (or 3400 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21452031 is about 4631.6337290421. The cubic root of 21452031 is about 277.8579359718.

Adding to 21452031 its reverse (13025412), we get a palindrome (34477443).

The spelling of 21452031 in words is "twenty-one million, four hundred fifty-two thousand, thirty-one".