42657661 has 4 divisors (see below), whose sum is σ = 42983424. Its totient is φ = 42331900.

The previous prime is 42657647. The next prime is 42657673. The reversal of 42657661 is 16675624.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 42657661 - 2⁹ = 42657149 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42657661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42657691) 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, 162685 + ... + 162946.

It is an arithmetic number, because the mean of its divisors is an integer number (10745856).

Almost surely, 2^42657661 is an apocalyptic number.

It is an amenable number.

42657661 is a deficient number, since it is larger than the sum of its proper divisors (325763).

42657661 is a wasteful number, since it uses less digits than its factorization.

42657661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325762.

The product of its digits is 60480, while the sum is 37.

The square root of 42657661 is about 6531.2832582885. The cubic root of 42657661 is about 349.4075992444.

It can be divided in two parts, 4 and 2657661, that added together give a triangular number (2657665 = T₂₃₀₅).

The spelling of 42657661 in words is "forty-two million, six hundred fifty-seven thousand, six hundred sixty-one".