161255344440 has 32 divisors (see below), whose sum is σ = 483766033680. Its totient is φ = 43001425152.

The previous prime is 161255344417. The next prime is 161255344463. The reversal of 161255344440 is 44443552161.

It is an interprime number because it is at equal distance from previous prime (161255344417) and next prime (161255344463).

It is a super-2 number, since 2×161255344440² (a number of 23 digits) contains 22 as substring.

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, 671897149 + ... + 671897388.

Almost surely, 2^161255344440 is an apocalyptic number.

161255344440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161255344440 is an abundant number, since it is smaller than the sum of its proper divisors (322510689240).

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

161255344440 is a wasteful number, since it uses less digits than its factorization.

161255344440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343794551 (or 1343794547 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 39.

The spelling of 161255344440 in words is "one hundred sixty-one billion, two hundred fifty-five million, three hundred forty-four thousand, four hundred forty".