42780731 has 8 divisors (see below), whose sum is σ = 49221600. Its totient is φ = 36422208.

The previous prime is 42780707. The next prime is 42780779. The reversal of 42780731 is 13708724.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 42780731 - 2¹⁰ = 42779707 is a prime.

It is a super-2 number, since 2×42780731² = 3660381889788722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42780781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19466 + ... + 21551.

It is an arithmetic number, because the mean of its divisors is an integer number (6152700).

Almost surely, 2^42780731 is an apocalyptic number.

42780731 is a deficient number, since it is larger than the sum of its proper divisors (6440869).

42780731 is a wasteful number, since it uses less digits than its factorization.

42780731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41173.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 42780731 is about 6540.6980514315. The cubic root of 42780731 is about 349.7432974855.

The spelling of 42780731 in words is "forty-two million, seven hundred eighty thousand, seven hundred thirty-one".