542365661 has 4 divisors (see below), whose sum is σ = 544734300. Its totient is φ = 539997024.

The previous prime is 542365643. The next prime is 542365693. The reversal of 542365661 is 166563245.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 392792761 + 149572900 = 19819^2 + 12230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-542365661 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 (542365631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1183976 + ... + 1184433.

It is an arithmetic number, because the mean of its divisors is an integer number (136183575).

Almost surely, 2^542365661 is an apocalyptic number.

It is an amenable number.

542365661 is a deficient number, since it is larger than the sum of its proper divisors (2368639).

542365661 is a wasteful number, since it uses less digits than its factorization.

542365661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2368638.

The product of its digits is 129600, while the sum is 38.

The square root of 542365661 is about 23288.7453719603. The cubic root of 542365661 is about 815.5126993469.

The spelling of 542365661 in words is "five hundred forty-two million, three hundred sixty-five thousand, six hundred sixty-one".