72181236 has 24 divisors (see below), whose sum is σ = 169916544. Its totient is φ = 23847040.

The previous prime is 72181229. The next prime is 72181253. The reversal of 72181236 is 63218127.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25260 + ... + 27971.

It is an arithmetic number, because the mean of its divisors is an integer number (7079856).

Almost surely, 2^72181236 is an apocalyptic number.

It is an amenable number.

72181236 is an abundant number, since it is smaller than the sum of its proper divisors (97735308).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72181236 is a wasteful number, since it uses less digits than its factorization.

72181236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53351 (or 53349 counting only the distinct ones).

The product of its digits is 4032, while the sum is 30.

The square root of 72181236 is about 8495.9540959212. The cubic root of 72181236 is about 416.3655333151.

The spelling of 72181236 in words is "seventy-two million, one hundred eighty-one thousand, two hundred thirty-six".