47421981 has 6 divisors (see below), whose sum is σ = 68498430. Its totient is φ = 31614648.

The previous prime is 47421977. The next prime is 47422009. The reversal of 47421981 is 18912474.

It can be written as a sum of positive squares in only one way, i.e., 33246756 + 14175225 = 5766^2 + 3765^2 .

It is not a de Polignac number, because 47421981 - 2² = 47421977 is a prime.

It is a super-2 number, since 2×47421981² = 4497688563928722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47421961) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2634546 + ... + 2634563.

It is an arithmetic number, because the mean of its divisors is an integer number (11416405).

Almost surely, 2^47421981 is an apocalyptic number.

It is an amenable number.

47421981 is a deficient number, since it is larger than the sum of its proper divisors (21076449).

47421981 is a wasteful number, since it uses less digits than its factorization.

47421981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5269115 (or 5269112 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 47421981 is about 6886.3619567955. The cubic root of 47421981 is about 361.9594314701.

The spelling of 47421981 in words is "forty-seven million, four hundred twenty-one thousand, nine hundred eighty-one".