400561560 has 192 divisors, whose sum is σ = 1552711680. Its totient is φ = 87563520.

The previous prime is 400561549. The next prime is 400561573. The reversal of 400561560 is 65165004.

It is a happy number.

400561560 is a `hidden beast` number, since 40 + 0 + 5 + 61 + 560 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 54505 + ... + 61415.

It is an arithmetic number, because the mean of its divisors is an integer number (8087040).

Almost surely, 2^400561560 is an apocalyptic number.

400561560 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400561560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (776355840).

400561560 is an abundant number, since it is smaller than the sum of its proper divisors (1152150120).

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

400561560 is a wasteful number, since it uses less digits than its factorization.

400561560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6958 (or 6951 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 400561560 is about 20014.0340761177. The cubic root of 400561560 is about 737.1509392866.

It can be divided in two parts, 40056 and 1560, that added together give a triangular number (41616 = T₂₈₈).

The spelling of 400561560 in words is "four hundred million, five hundred sixty-one thousand, five hundred sixty".