1216752765 has 8 divisors (see below), whose sum is σ = 1946804448. Its totient is φ = 648934800.

The previous prime is 1216752743. The next prime is 1216752767. The reversal of 1216752765 is 5672576121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1216752765 - 2⁷ = 1216752637 is a prime.

It is a super-2 number, since 2×1216752765² = 2960974582270290450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216752767) 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, 40558411 + ... + 40558440.

It is an arithmetic number, because the mean of its divisors is an integer number (243350556).

Almost surely, 2^1216752765 is an apocalyptic number.

1216752765 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1216752765 is a deficient number, since it is larger than the sum of its proper divisors (730051683).

1216752765 is an equidigital number, since it uses as much as digits as its factorization.

1216752765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81116859.

The product of its digits is 176400, while the sum is 42.

The square root of 1216752765 is about 34881.9833868431. The cubic root of 1216752765 is about 1067.5808639864.

The spelling of 1216752765 in words is "one billion, two hundred sixteen million, seven hundred fifty-two thousand, seven hundred sixty-five".