161563256680 has 48 divisors (see below), whose sum is σ = 422867100420. Its totient is φ = 55393115904.

The previous prime is 161563256671. The next prime is 161563256689. The reversal of 161563256680 is 86652365161.

It is an interprime number because it is at equal distance from previous prime (161563256671) and next prime (161563256689).

It can be written as a sum of positive squares in 2 ways, for example, as 156387029764 + 5176226916 = 395458^2 + 71946^2 .

It is a super-2 number, since 2×161563256680² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (161563256689) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41213157 + ... + 41217076.

Almost surely, 2^161563256680 is an apocalyptic number.

161563256680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161563256680 is an abundant number, since it is smaller than the sum of its proper divisors (261303843740).

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

161563256680 is a wasteful number, since it uses less digits than its factorization.

161563256680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82430258 (or 82430247 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 49.

The spelling of 161563256680 in words is "one hundred sixty-one billion, five hundred sixty-three million, two hundred fifty-six thousand, six hundred eighty".