147721531 has 2 divisors, whose sum is σ = 147721532. Its totient is φ = 147721530.

The previous prime is 147721507. The next prime is 147721549. The reversal of 147721531 is 135127741.

147721531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 147721531 - 2⁵ = 147721499 is a prime.

It is a super-2 number, since 2×147721531² = 43643301441967922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 147721493 and 147721502.

It is not a weakly prime, because it can be changed into another prime (147701531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 73860765 + 73860766.

It is an arithmetic number, because the mean of its divisors is an integer number (73860766).

Almost surely, 2^147721531 is an apocalyptic number.

147721531 is a deficient number, since it is larger than the sum of its proper divisors (1).

147721531 is an equidigital number, since it uses as much as digits as its factorization.

147721531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5880, while the sum is 31.

The square root of 147721531 is about 12154.0746665470. The cubic root of 147721531 is about 528.6252862892.

The spelling of 147721531 in words is "one hundred forty-seven million, seven hundred twenty-one thousand, five hundred thirty-one".