47942821 has 4 divisors (see below), whose sum is σ = 48618144. Its totient is φ = 47267500.

The previous prime is 47942813. The next prime is 47942837. The reversal of 47942821 is 12824974.

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 47942821 - 2³ = 47942813 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 (47942801) 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, 337555 + ... + 337696.

It is an arithmetic number, because the mean of its divisors is an integer number (12154536).

Almost surely, 2^47942821 is an apocalyptic number.

It is an amenable number.

47942821 is a deficient number, since it is larger than the sum of its proper divisors (675323).

47942821 is an equidigital number, since it uses as much as digits as its factorization.

47942821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 675322.

The product of its digits is 32256, while the sum is 37.

The square root of 47942821 is about 6924.0754617494. The cubic root of 47942821 is about 363.2797540909.

The spelling of 47942821 in words is "forty-seven million, nine hundred forty-two thousand, eight hundred twenty-one".