161553236 has 24 divisors (see below), whose sum is σ = 311550624. Its totient is φ = 72828000.

The previous prime is 161553233. The next prime is 161553263. The reversal of 161553236 is 632355161.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161553233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33890 + ... + 38361.

It is an arithmetic number, because the mean of its divisors is an integer number (12981276).

Almost surely, 2^161553236 is an apocalyptic number.

It is an amenable number.

161553236 is a deficient number, since it is larger than the sum of its proper divisors (149997388).

161553236 is a wasteful number, since it uses less digits than its factorization.

161553236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72311 (or 72309 counting only the distinct ones).

The product of its digits is 16200, while the sum is 32.

The square root of 161553236 is about 12710.3593969644. The cubic root of 161553236 is about 544.6345905080.

It can be divided in two parts, 16155 and 3236, that added together give a palindrome (19391).

The spelling of 161553236 in words is "one hundred sixty-one million, five hundred fifty-three thousand, two hundred thirty-six".