47972781 has 6 divisors (see below), whose sum is σ = 69294030. Its totient is φ = 31981848.

The previous prime is 47972773. The next prime is 47972807. The reversal of 47972781 is 18727974.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 32832900 + 15139881 = 5730^2 + 3891^2 .

It is not a de Polignac number, because 47972781 - 2³ = 47972773 is a prime.

It is a super-2 number, since 2×47972781² = 4602775433747922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47972711) 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, 2665146 + ... + 2665163.

It is an arithmetic number, because the mean of its divisors is an integer number (11549005).

Almost surely, 2^47972781 is an apocalyptic number.

It is an amenable number.

47972781 is a deficient number, since it is larger than the sum of its proper divisors (21321249).

47972781 is a wasteful number, since it uses less digits than its factorization.

47972781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5330315 (or 5330312 counting only the distinct ones).

The product of its digits is 197568, while the sum is 45.

The square root of 47972781 is about 6926.2385895954. The cubic root of 47972781 is about 363.3554108479.

The spelling of 47972781 in words is "forty-seven million, nine hundred seventy-two thousand, seven hundred eighty-one".