1211889497 has 16 divisors (see below), whose sum is σ = 1542992640. Its totient is φ = 925791552.

The previous prime is 1211889491. The next prime is 1211889517. The reversal of 1211889497 is 7949881121.

It is a happy number.

It is not a de Polignac number, because 1211889497 - 2⁸ = 1211889241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211889491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 226973 + ... + 232250.

It is an arithmetic number, because the mean of its divisors is an integer number (96437040).

Almost surely, 2^1211889497 is an apocalyptic number.

It is an amenable number.

1211889497 is a deficient number, since it is larger than the sum of its proper divisors (331103143).

1211889497 is a wasteful number, since it uses less digits than its factorization.

1211889497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459272.

The product of its digits is 290304, while the sum is 50.

The square root of 1211889497 is about 34812.2032770119. The cubic root of 1211889497 is about 1066.1566183342.

The spelling of 1211889497 in words is "one billion, two hundred eleven million, eight hundred eighty-nine thousand, four hundred ninety-seven".