451535220021 has 4 divisors (see below), whose sum is σ = 602046960032. Its totient is φ = 301023480012.

The previous prime is 451535219977. The next prime is 451535220023. The reversal of 451535220021 is 120022535154.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 451535220021 - 2⁶ = 451535219957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (451535220023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75255870001 + ... + 75255870006.

It is an arithmetic number, because the mean of its divisors is an integer number (150511740008).

Almost surely, 2^451535220021 is an apocalyptic number.

It is an amenable number.

451535220021 is a deficient number, since it is larger than the sum of its proper divisors (150511740011).

451535220021 is a wasteful number, since it uses less digits than its factorization.

451535220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150511740010.

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 451535220021 its reverse (120022535154), we get a palindrome (571557755175).

The spelling of 451535220021 in words is "four hundred fifty-one billion, five hundred thirty-five million, two hundred twenty thousand, twenty-one".