161253405 has 12 divisors (see below), whose sum is σ = 279505980. Its totient is φ = 86001792.

The previous prime is 161253383. The next prime is 161253409. The reversal of 161253405 is 504352161.

161253405 is a `hidden beast` number, since 1 + 6 + 1 + 253 + 405 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 71723961 + 89529444 = 8469^2 + 9462^2 .

It is not a de Polignac number, because 161253405 - 2¹⁰ = 161252381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161253409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1791660 + ... + 1791749.

It is an arithmetic number, because the mean of its divisors is an integer number (23292165).

Almost surely, 2^161253405 is an apocalyptic number.

161253405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161253405 is a deficient number, since it is larger than the sum of its proper divisors (118252575).

161253405 is a wasteful number, since it uses less digits than its factorization.

161253405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3583420 (or 3583417 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 161253405 is about 12698.5591702366. The cubic root of 161253405 is about 544.2974478515.

The spelling of 161253405 in words is "one hundred sixty-one million, two hundred fifty-three thousand, four hundred five".