54381661 has 2 divisors, whose sum is σ = 54381662. Its totient is φ = 54381660.

The previous prime is 54381659. The next prime is 54381697. The reversal of 54381661 is 16618345.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33860761 + 20520900 = 5819^2 + 4530^2 .

It is a cyclic number.

It is not a de Polignac number, because 54381661 - 2¹ = 54381659 is a prime.

Together with 54381659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (54381611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27190830 + 27190831.

It is an arithmetic number, because the mean of its divisors is an integer number (27190831).

Almost surely, 2^54381661 is an apocalyptic number.

It is an amenable number.

54381661 is a deficient number, since it is larger than the sum of its proper divisors (1).

54381661 is an equidigital number, since it uses as much as digits as its factorization.

54381661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 34.

The square root of 54381661 is about 7374.3922461448. The cubic root of 54381661 is about 378.8647117747.

The spelling of 54381661 in words is "fifty-four million, three hundred eighty-one thousand, six hundred sixty-one".