20321451 has 6 divisors (see below), whose sum is σ = 29353220. Its totient is φ = 13547628.

The previous prime is 20321447. The next prime is 20321537. The reversal of 20321451 is 15412302.

It is not a de Polignac number, because 20321451 - 2² = 20321447 is a prime.

It is a super-2 number, since 2×20321451² = 825922741490802, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20321401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1128961 + ... + 1128978.

Almost surely, 2^20321451 is an apocalyptic number.

20321451 is a deficient number, since it is larger than the sum of its proper divisors (9031769).

20321451 is a wasteful number, since it uses less digits than its factorization.

20321451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2257945 (or 2257942 counting only the distinct ones).

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

The square root of 20321451 is about 4507.9320092477. The cubic root of 20321451 is about 272.8882930651. Note that the first 3 decimals are identical.

Adding to 20321451 its reverse (15412302), we get a palindrome (35733753).

The spelling of 20321451 in words is "twenty million, three hundred twenty-one thousand, four hundred fifty-one".