1211969745 has 48 divisors (see below), whose sum is σ = 2403498240. Its totient is φ = 553433472.

The previous prime is 1211969719. The next prime is 1211969753. The reversal of 1211969745 is 5479691121.

It is not a de Polignac number, because 1211969745 - 2⁵ = 1211969713 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1211969745.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 414027 + ... + 416943.

It is an arithmetic number, because the mean of its divisors is an integer number (50072880).

Almost surely, 2^1211969745 is an apocalyptic number.

1211969745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1211969745 is a deficient number, since it is larger than the sum of its proper divisors (1191528495).

1211969745 is a wasteful number, since it uses less digits than its factorization.

1211969745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4254 (or 4251 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 1211969745 is about 34813.3558422626. The cubic root of 1211969745 is about 1066.1801504709.

The spelling of 1211969745 in words is "one billion, two hundred eleven million, nine hundred sixty-nine thousand, seven hundred forty-five".