42821949 has 4 divisors (see below), whose sum is σ = 57095936. Its totient is φ = 28547964.

The previous prime is 42821903. The next prime is 42821959. The reversal of 42821949 is 94912824.

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 de Polignac number, because none of the positive numbers 2^k-42821949 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 (42821959) 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, 7136989 + ... + 7136994.

It is an arithmetic number, because the mean of its divisors is an integer number (14273984).

Almost surely, 2^42821949 is an apocalyptic number.

It is an amenable number.

42821949 is a deficient number, since it is larger than the sum of its proper divisors (14273987).

42821949 is a wasteful number, since it uses less digits than its factorization.

42821949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14273986.

The product of its digits is 41472, while the sum is 39.

The square root of 42821949 is about 6543.8481797792. The cubic root of 42821949 is about 349.8555839571.

The spelling of 42821949 in words is "forty-two million, eight hundred twenty-one thousand, nine hundred forty-nine".