16551601 has 4 divisors (see below), whose sum is σ = 18056304. Its totient is φ = 15046900.

The previous prime is 16551599. The next prime is 16551629. The reversal of 16551601 is 10615561.

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 not a de Polignac number, because 16551601 - 2¹ = 16551599 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16551631) 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, 752335 + ... + 752356.

It is an arithmetic number, because the mean of its divisors is an integer number (4514076).

Almost surely, 2^16551601 is an apocalyptic number.

16551601 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16551601 is a deficient number, since it is larger than the sum of its proper divisors (1504703).

16551601 is a wasteful number, since it uses less digits than its factorization.

16551601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1504702.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 16551601 is about 4068.3658881669. The cubic root of 16551601 is about 254.8472800778.

The spelling of 16551601 in words is "sixteen million, five hundred fifty-one thousand, six hundred one".