1361221732440 has 128 divisors (see below), whose sum is σ = 4633946496000. Its totient is φ = 355269204864.

The previous prime is 1361221732391. The next prime is 1361221732447. The reversal of 1361221732440 is 442371221631.

1361221732440 is a `hidden beast` number, since 1 + 3 + 612 + 2 + 1 + 7 + 32 + 4 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1361221732395 and 1361221732404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361221732447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13357650 + ... + 13459169.

It is an arithmetic number, because the mean of its divisors is an integer number (36202707000).

Almost surely, 2^{1361221732440} is an apocalyptic number.

1361221732440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1361221732440 is an abundant number, since it is smaller than the sum of its proper divisors (3272724763560).

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

1361221732440 is a wasteful number, since it uses less digits than its factorization.

1361221732440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26816886 (or 26816876 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The spelling of 1361221732440 in words is "one trillion, three hundred sixty-one billion, two hundred twenty-one million, seven hundred thirty-two thousand, four hundred forty".