161972424 has 48 divisors (see below), whose sum is σ = 453807900. Its totient is φ = 52128384.

The previous prime is 161972423. The next prime is 161972431. The reversal of 161972424 is 424279161.

It is a happy number.

161972424 is a `hidden beast` number, since 161 + 9 + 72 + 424 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 143568324 + 18404100 = 11982^2 + 4290^2 .

It is a super-2 number, since 2×161972424² = 52470132272871552, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (161972423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36699 + ... + 40874.

Almost surely, 2^161972424 is an apocalyptic number.

It is an amenable number.

161972424 is an abundant number, since it is smaller than the sum of its proper divisors (291835476).

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

161972424 is a wasteful number, since it uses less digits than its factorization.

161972424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77614 (or 77607 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 161972424 is about 12726.8387276652. The cubic root of 161972424 is about 545.1052446639.

The spelling of 161972424 in words is "one hundred sixty-one million, nine hundred seventy-two thousand, four hundred twenty-four".