1296216072 has 24 divisors (see below), whose sum is σ = 3510585390. Its totient is φ = 432072000.

The previous prime is 1296216067. The next prime is 1296216137. The reversal of 1296216072 is 2706126921.

1296216072 is a `hidden beast` number, since 1 + 29 + 6 + 21 + 607 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1252735236 + 43480836 = 35394^2 + 6594^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×1296216072² = 3360352210622218368, which contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9001429 + ... + 9001572.

Almost surely, 2^1296216072 is an apocalyptic number.

1296216072 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1296216072 is an abundant number, since it is smaller than the sum of its proper divisors (2214369318).

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

1296216072 is a wasteful number, since it uses less digits than its factorization.

1296216072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18003013 (or 18003006 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 1296216072 is about 36003.0008749271. Note that the first 3 decimals coincide. The cubic root of 1296216072 is about 1090.3329432090.

The spelling of 1296216072 in words is "one billion, two hundred ninety-six million, two hundred sixteen thousand, seventy-two".