12420551 has 8 divisors (see below), whose sum is σ = 14592144. Its totient is φ = 10422720.

The previous prime is 12420521. The next prime is 12420571. The reversal of 12420551 is 15502421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12420551 - 2⁶ = 12420487 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 (12420511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43286 + ... + 43571.

It is an arithmetic number, because the mean of its divisors is an integer number (1824018).

Almost surely, 2^12420551 is an apocalyptic number.

12420551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12420551 is a deficient number, since it is larger than the sum of its proper divisors (2171593).

12420551 is a wasteful number, since it uses less digits than its factorization.

12420551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86881.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 12420551 is about 3524.2802101990. The cubic root of 12420551 is about 231.5867034783.

Adding to 12420551 its reverse (15502421), we get a palindrome (27922972).

The spelling of 12420551 in words is "twelve million, four hundred twenty thousand, five hundred fifty-one".