15491601 has 8 divisors (see below), whose sum is σ = 22950560. Its totient is φ = 10327716.

The previous prime is 15491591. The next prime is 15491603. The reversal of 15491601 is 10619451.

15491601 is a `hidden beast` number, since 1 + 54 + 9 + 1 + 601 = 666.

It is not a de Polignac number, because 15491601 - 2¹³ = 15483409 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 573763 = 15491601 / (1 + 5 + 4 + 9 + 1 + 6 + 0 + 1).

It is a Duffinian number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (15491603) 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, 286855 + ... + 286908.

It is an arithmetic number, because the mean of its divisors is an integer number (2868820).

Almost surely, 2^15491601 is an apocalyptic number.

It is an amenable number.

15491601 is a deficient number, since it is larger than the sum of its proper divisors (7458959).

15491601 is an equidigital number, since it uses as much as digits as its factorization.

15491601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573772 (or 573766 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 15491601 is about 3935.9371184001. The cubic root of 15491601 is about 249.2865042994.

The spelling of 15491601 in words is "fifteen million, four hundred ninety-one thousand, six hundred one".