1243645564 has 12 divisors (see below), whose sum is σ = 2487291184. Its totient is φ = 532990944.

The previous prime is 1243645549. The next prime is 1243645567. The reversal of 1243645564 is 4655463421.

1243645564 is an admirable number.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243645567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22207929 + ... + 22207984.

Almost surely, 2^1243645564 is an apocalyptic number.

1243645564 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1243645564 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1243645564 is a wasteful number, since it uses less digits than its factorization.

1243645564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44415924 (or 44415922 counting only the distinct ones).

The product of its digits is 345600, while the sum is 40.

The square root of 1243645564 is about 35265.3592637307. The cubic root of 1243645564 is about 1075.3888808307.

The spelling of 1243645564 in words is "one billion, two hundred forty-three million, six hundred forty-five thousand, five hundred sixty-four".