15520001 has 4 divisors (see below), whose sum is σ = 17737152. Its totient is φ = 13302852.

The previous prime is 15519971. The next prime is 15520007. The reversal of 15520001 is 10002551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 15520001 - 2²² = 11325697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15520007) 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, 1108565 + ... + 1108578.

It is an arithmetic number, because the mean of its divisors is an integer number (4434288).

Almost surely, 2^15520001 is an apocalyptic number.

It is an amenable number.

15520001 is a deficient number, since it is larger than the sum of its proper divisors (2217151).

15520001 is an equidigital number, since it uses as much as digits as its factorization.

15520001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2217150.

The product of its (nonzero) digits is 50, while the sum is 14.

The square root of 15520001 is about 3939.5432476367. The cubic root of 15520001 is about 249.4387462532.

Adding to 15520001 its reverse (10002551), we get a palindrome (25522552).

The spelling of 15520001 in words is "fifteen million, five hundred twenty thousand, one".