551432421 has 16 divisors (see below), whose sum is σ = 859934400. Its totient is φ = 348272784.

The previous prime is 551432377. The next prime is 551432443. The reversal of 551432421 is 124234155.

It is not a de Polignac number, because 551432421 - 2¹³ = 551424229 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551431421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 536946 + ... + 537971.

It is an arithmetic number, because the mean of its divisors is an integer number (53745900).

Almost surely, 2^551432421 is an apocalyptic number.

It is an amenable number.

551432421 is a deficient number, since it is larger than the sum of its proper divisors (308501979).

551432421 is a wasteful number, since it uses less digits than its factorization.

551432421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1074945 (or 1074939 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 551432421 is about 23482.5982591365. The cubic root of 551432421 is about 820.0319346080.

Adding to 551432421 its reverse (124234155), we get a palindrome (675666576).

The spelling of 551432421 in words is "five hundred fifty-one million, four hundred thirty-two thousand, four hundred twenty-one".