147311981 has 2 divisors, whose sum is σ = 147311982. Its totient is φ = 147311980.

The previous prime is 147311951. The next prime is 147312013. The reversal of 147311981 is 189113741.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146773225 + 538756 = 12115^2 + 734^2 .

It is a cyclic number.

It is not a de Polignac number, because 147311981 - 2⁶ = 147311917 is a prime.

It is a super-2 number, since 2×147311981² = 43401639492288722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (147311951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 73655990 + 73655991.

It is an arithmetic number, because the mean of its divisors is an integer number (73655991).

Almost surely, 2^147311981 is an apocalyptic number.

It is an amenable number.

147311981 is a deficient number, since it is larger than the sum of its proper divisors (1).

147311981 is an equidigital number, since it uses as much as digits as its factorization.

147311981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 35.

The square root of 147311981 is about 12137.2147134341. The cubic root of 147311981 is about 528.1363057277.

The spelling of 147311981 in words is "one hundred forty-seven million, three hundred eleven thousand, nine hundred eighty-one".