16557901 has 6 divisors (see below), whose sum is σ = 16861706. Its totient is φ = 16255200.

The previous prime is 16557887. The next prime is 16557913. The reversal of 16557901 is 10975561.

It can be written as a sum of positive squares in 3 ways, for example, as 276676 + 16281225 = 526^2 + 4035^2 .

It is not a de Polignac number, because 16557901 - 2²¹ = 14460749 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 (16557991) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 31521 + ... + 32041.

Almost surely, 2^16557901 is an apocalyptic number.

It is an amenable number.

16557901 is a deficient number, since it is larger than the sum of its proper divisors (303805).

16557901 is an frugal number, since it uses more digits than its factorization.

16557901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1103 (or 582 counting only the distinct ones).

The product of its (nonzero) digits is 9450, while the sum is 34.

The square root of 16557901 is about 4069.1400811474. The cubic root of 16557901 is about 254.8796099655.

The spelling of 16557901 in words is "sixteen million, five hundred fifty-seven thousand, nine hundred one".