42920781 has 8 divisors (see below), whose sum is σ = 57559200. Its totient is φ = 28448112.

The previous prime is 42920743. The next prime is 42920819. The reversal of 42920781 is 18702924.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (42920743) and next prime (42920819).

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

It is not a de Polignac number, because 42920781 - 2⁷ = 42920653 is a prime.

It is a super-2 number, since 2×42920781² = 3684386883299922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42920701) 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, 40831 + ... + 41868.

It is an arithmetic number, because the mean of its divisors is an integer number (7194900).

Almost surely, 2^42920781 is an apocalyptic number.

It is an amenable number.

42920781 is a deficient number, since it is larger than the sum of its proper divisors (14638419).

42920781 is a wasteful number, since it uses less digits than its factorization.

42920781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82875.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 42920781 is about 6551.3953475576. The cubic root of 42920781 is about 350.1245298367.

The spelling of 42920781 in words is "forty-two million, nine hundred twenty thousand, seven hundred eighty-one".