47218731 has 8 divisors (see below), whose sum is σ = 71952384. Its totient is φ = 26982120.

The previous prime is 47218729. The next prime is 47218739. The reversal of 47218731 is 13781274.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 47218731 - 2¹ = 47218729 is a prime.

It is a super-2 number, since 2×47218731² = 4459217114500722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 47218692 and 47218701.

It is not an unprimeable number, because it can be changed into a prime (47218739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1124235 + ... + 1124276.

It is an arithmetic number, because the mean of its divisors is an integer number (8994048).

Almost surely, 2^47218731 is an apocalyptic number.

47218731 is a deficient number, since it is larger than the sum of its proper divisors (24733653).

47218731 is a wasteful number, since it uses less digits than its factorization.

47218731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2248521.

The product of its digits is 9408, while the sum is 33.

The square root of 47218731 is about 6871.5886809383. The cubic root of 47218731 is about 361.4415730982.

The spelling of 47218731 in words is "forty-seven million, two hundred eighteen thousand, seven hundred thirty-one".