1561400 has 48 divisors (see below), whose sum is σ = 3746040. Its totient is φ = 604800.

The previous prime is 1561393. The next prime is 1561421. The reversal of 1561400 is 41651.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7295 + ... + 7505.

2^1561400 is an apocalyptic number.

1561400 is a gapful number since it is divisible by the number (10) 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 1561400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1873020).

1561400 is an abundant number, since it is smaller than the sum of its proper divisors (2184640).

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

1561400 is a wasteful number, since it uses less digits than its factorization.

1561400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264 (or 255 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 1561400 is about 1249.5599225327. The cubic root of 1561400 is about 116.0124837932.

The spelling of 1561400 in words is "one million, five hundred sixty-one thousand, four hundred".