161251507155 has 16 divisors (see below), whose sum is σ = 258017185440. Its totient is φ = 85995879168.

The previous prime is 161251507121. The next prime is 161251507159. The reversal of 161251507155 is 551705152161.

It is a happy number.

It is not a de Polignac number, because 161251507155 - 2⁹ = 161251506643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161251507159) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28962 + ... + 568631.

It is an arithmetic number, because the mean of its divisors is an integer number (16126074090).

Almost surely, 2^161251507155 is an apocalyptic number.

161251507155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161251507155 is a deficient number, since it is larger than the sum of its proper divisors (96765678285).

161251507155 is a wasteful number, since it uses less digits than its factorization.

161251507155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615590.

The product of its (nonzero) digits is 52500, while the sum is 39.

The spelling of 161251507155 in words is "one hundred sixty-one billion, two hundred fifty-one million, five hundred seven thousand, one hundred fifty-five".