421400551 has 16 divisors (see below), whose sum is σ = 495710208. Its totient is φ = 353167200.

The previous prime is 421400527. The next prime is 421400557. The reversal of 421400551 is 155004124.

It is a cyclic number.

It is not a de Polignac number, because 421400551 - 2⁷ = 421400423 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 (421400557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154086 + ... + 156796.

It is an arithmetic number, because the mean of its divisors is an integer number (30981888).

Almost surely, 2^421400551 is an apocalyptic number.

421400551 is a deficient number, since it is larger than the sum of its proper divisors (74309657).

421400551 is a wasteful number, since it uses less digits than its factorization.

421400551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3822.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 421400551 is about 20528.0430387312. The cubic root of 421400551 is about 749.7187395737.

Adding to 421400551 its reverse (155004124), we get a palindrome (576404675).

The spelling of 421400551 in words is "four hundred twenty-one million, four hundred thousand, five hundred fifty-one".