54001661 has 4 divisors (see below), whose sum is σ = 61716192. Its totient is φ = 46287132.

The previous prime is 54001643. The next prime is 54001663. The reversal of 54001661 is 16610045.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16610045 = 5 ⋅3322009.

It is a cyclic number.

It is not a de Polignac number, because 54001661 - 2¹⁴ = 53985277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54001663) 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, 3857255 + ... + 3857268.

It is an arithmetic number, because the mean of its divisors is an integer number (15429048).

Almost surely, 2^54001661 is an apocalyptic number.

It is an amenable number.

54001661 is a deficient number, since it is larger than the sum of its proper divisors (7714531).

54001661 is an equidigital number, since it uses as much as digits as its factorization.

54001661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7714530.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 54001661 is about 7348.5822442155. The cubic root of 54001661 is about 377.9801903525.

The spelling of 54001661 in words is "fifty-four million, one thousand, six hundred sixty-one".