1005661400 has 24 divisors (see below), whose sum is σ = 2338163220. Its totient is φ = 402264480.

The previous prime is 1005661387. The next prime is 1005661403. The reversal of 1005661400 is 41665001.

It is a super-2 number, since 2×1005661400² = 2022709702899920000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1005661403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2513954 + ... + 2514353.

Almost surely, 2^1005661400 is an apocalyptic number.

1005661400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1005661400 is an abundant number, since it is smaller than the sum of its proper divisors (1332501820).

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

1005661400 is a wasteful number, since it uses less digits than its factorization.

1005661400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5028323 (or 5028314 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 1005661400 is about 31712.1648583000. The cubic root of 1005661400 is about 1001.8835832200.

The spelling of 1005661400 in words is "one billion, five million, six hundred sixty-one thousand, four hundred".