161225740 has 24 divisors (see below), whose sum is σ = 364618800. Its totient is φ = 59529408.

The previous prime is 161225723. The next prime is 161225777. The reversal of 161225740 is 47522161.

It is a junction number, because it is equal to n+sod(n) for n = 161225699 and 161225708.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 309790 + ... + 310309.

It is an arithmetic number, because the mean of its divisors is an integer number (15192450).

Almost surely, 2^161225740 is an apocalyptic number.

161225740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161225740 is an abundant number, since it is smaller than the sum of its proper divisors (203393060).

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

161225740 is a wasteful number, since it uses less digits than its factorization.

161225740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620121 (or 620119 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 161225740 is about 12697.4698267017. The cubic root of 161225740 is about 544.2663191029.

The spelling of 161225740 in words is "one hundred sixty-one million, two hundred twenty-five thousand, seven hundred forty".