1272163440 has 40 divisors (see below), whose sum is σ = 3943707408. Its totient is φ = 339243520.

The previous prime is 1272163433. The next prime is 1272163441. The reversal of 1272163440 is 443612721.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1272163398 and 1272163407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1272163441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2650101 + ... + 2650580.

Almost surely, 2^1272163440 is an apocalyptic number.

1272163440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1272163440 is an abundant number, since it is smaller than the sum of its proper divisors (2671543968).

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

1272163440 is a wasteful number, since it uses less digits than its factorization.

1272163440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5300697 (or 5300691 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 1272163440 is about 35667.4002416773. The cubic root of 1272163440 is about 1083.5467075304.

The spelling of 1272163440 in words is "one billion, two hundred seventy-two million, one hundred sixty-three thousand, four hundred forty".