47817990 has 72 divisors (see below), whose sum is σ = 136687824. Its totient is φ = 11589600.

The previous prime is 47817983. The next prime is 47817997. The reversal of 47817990 is 9971874.

47817990 is a `hidden beast` number, since 478 + 179 + 9 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (47817983) and next prime (47817997).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47817997) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 8695 + ... + 13085.

It is an arithmetic number, because the mean of its divisors is an integer number (1898442).

Almost surely, 2^47817990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 47817990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68343912).

47817990 is an abundant number, since it is smaller than the sum of its proper divisors (88869834).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

47817990 is a wasteful number, since it uses less digits than its factorization.

47817990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4426 (or 4412 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 45.

The square root of 47817990 is about 6915.0553143124. The cubic root of 47817990 is about 362.9641837941.

The spelling of 47817990 in words is "forty-seven million, eight hundred seventeen thousand, nine hundred ninety".