15400401444 has 36 divisors (see below), whose sum is σ = 38991942444. Its totient is φ = 5125139712.

The previous prime is 15400401403. The next prime is 15400401449. The reversal of 15400401444 is 44410400451.

It can be written as a sum of positive squares in 2 ways, for example, as 2775182400 + 12625219044 = 52680^2 + 112362^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (15400401449) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 324457 + ... + 368880.

Almost surely, 2^15400401444 is an apocalyptic number.

It is an amenable number.

15400401444 is an abundant number, since it is smaller than the sum of its proper divisors (23591541000).

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

15400401444 is a wasteful number, since it uses less digits than its factorization.

15400401444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693964 (or 693959 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

Adding to 15400401444 its reverse (44410400451), we get a palindrome (59810801895).

The spelling of 15400401444 in words is "fifteen billion, four hundred million, four hundred one thousand, four hundred forty-four".