47815987 has 2 divisors, whose sum is σ = 47815988. Its totient is φ = 47815986.

The previous prime is 47815979. The next prime is 47815991. The reversal of 47815987 is 78951874.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 47815987 - 2³ = 47815979 is a prime.

It is a super-2 number, since 2×47815987² = 4572737225568338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 47815987.

It is not a weakly prime, because it can be changed into another prime (47815087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23907993 + 23907994.

It is an arithmetic number, because the mean of its divisors is an integer number (23907994).

Almost surely, 2^47815987 is an apocalyptic number.

47815987 is a deficient number, since it is larger than the sum of its proper divisors (1).

47815987 is an equidigital number, since it uses as much as digits as its factorization.

47815987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 564480, while the sum is 49.

The square root of 47815987 is about 6914.9104838747. The cubic root of 47815987 is about 362.9591157753.

The spelling of 47815987 in words is "forty-seven million, eight hundred fifteen thousand, nine hundred eighty-seven".