155216065531 has 2 divisors, whose sum is σ = 155216065532. Its totient is φ = 155216065530.

The previous prime is 155216065469. The next prime is 155216065553. The reversal of 155216065531 is 135560612551.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 155216065531 - 2⁹ = 155216065019 is a prime.

It is a super-2 number, since 2×155216065531² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (155216065591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77608032765 + 77608032766.

It is an arithmetic number, because the mean of its divisors is an integer number (77608032766).

Almost surely, 2^155216065531 is an apocalyptic number.

155216065531 is a deficient number, since it is larger than the sum of its proper divisors (1).

155216065531 is an equidigital number, since it uses as much as digits as its factorization.

155216065531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 135000, while the sum is 40.

The spelling of 155216065531 in words is "one hundred fifty-five billion, two hundred sixteen million, sixty-five thousand, five hundred thirty-one".