149779423681 has 2 divisors, whose sum is σ = 149779423682. Its totient is φ = 149779423680.

The previous prime is 149779423679. The next prime is 149779423687. The reversal of 149779423681 is 186324977941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149182110081 + 597313600 = 386241^2 + 24440^2 .

It is an emirp because it is prime and its reverse (186324977941) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 149779423681 - 2¹ = 149779423679 is a prime.

It is a super-2 number, since 2×149779423681² (a number of 23 digits) contains 22 as substring.

Together with 149779423679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (149779423687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74889711840 + 74889711841.

It is an arithmetic number, because the mean of its divisors is an integer number (74889711841).

Almost surely, 2^149779423681 is an apocalyptic number.

It is an amenable number.

149779423681 is a deficient number, since it is larger than the sum of its proper divisors (1).

149779423681 is an equidigital number, since it uses as much as digits as its factorization.

149779423681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18289152, while the sum is 61.

The spelling of 149779423681 in words is "one hundred forty-nine billion, seven hundred seventy-nine million, four hundred twenty-three thousand, six hundred eighty-one".