420534551 has 4 divisors (see below), whose sum is σ = 421221192. Its totient is φ = 419847912.

The previous prime is 420534533. The next prime is 420534577. The reversal of 420534551 is 155435024.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420534551 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 (420533551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 342401 + ... + 343626.

It is an arithmetic number, because the mean of its divisors is an integer number (105305298).

Almost surely, 2^420534551 is an apocalyptic number.

420534551 is a deficient number, since it is larger than the sum of its proper divisors (686641).

420534551 is an equidigital number, since it uses as much as digits as its factorization.

420534551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686640.

The product of its (nonzero) digits is 12000, while the sum is 29.

The square root of 420534551 is about 20506.9390938775. The cubic root of 420534551 is about 749.2048170619.

Adding to 420534551 its reverse (155435024), we get a palindrome (575969575).

The spelling of 420534551 in words is "four hundred twenty million, five hundred thirty-four thousand, five hundred fifty-one".