15551401 has 4 divisors (see below), whose sum is σ = 15806404. Its totient is φ = 15296400.

The previous prime is 15551369. The next prime is 15551467. The reversal of 15551401 is 10415551.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2418025 + 13133376 = 1555^2 + 3624^2 .

It is a cyclic number.

It is not a de Polignac number, because 15551401 - 2⁵ = 15551369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15554401) 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, 127410 + ... + 127531.

It is an arithmetic number, because the mean of its divisors is an integer number (3951601).

Almost surely, 2^15551401 is an apocalyptic number.

It is an amenable number.

15551401 is a deficient number, since it is larger than the sum of its proper divisors (255003).

15551401 is an equidigital number, since it uses as much as digits as its factorization.

15551401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255002.

The product of its (nonzero) digits is 500, while the sum is 22.

The square root of 15551401 is about 3943.5264675161. The cubic root of 15551401 is about 249.6068540692.

Adding to 15551401 its reverse (10415551), we get a palindrome (25966952).

The spelling of 15551401 in words is "fifteen million, five hundred fifty-one thousand, four hundred one".