201621451 has 2 divisors, whose sum is σ = 201621452. Its totient is φ = 201621450.

The previous prime is 201621437. The next prime is 201621457. The reversal of 201621451 is 154126102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 201621451 - 2⁵ = 201621419 is a prime.

It is not a weakly prime, because it can be changed into another prime (201621457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100810725 + 100810726.

It is an arithmetic number, because the mean of its divisors is an integer number (100810726).

Almost surely, 2^201621451 is an apocalyptic number.

201621451 is a deficient number, since it is larger than the sum of its proper divisors (1).

201621451 is an equidigital number, since it uses as much as digits as its factorization.

201621451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 201621451 is about 14199.3468511759. The cubic root of 201621451 is about 586.3796797456.

Adding to 201621451 its reverse (154126102), we get a palindrome (355747553).

The spelling of 201621451 in words is "two hundred one million, six hundred twenty-one thousand, four hundred fifty-one".