1219891051 has 2 divisors, whose sum is σ = 1219891052. Its totient is φ = 1219891050.

The previous prime is 1219891033. The next prime is 1219891087. The reversal of 1219891051 is 1501989121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1219891051 - 2⁵ = 1219891019 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1219891051.

It is not a weakly prime, because it can be changed into another prime (1219891091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609945525 + 609945526.

It is an arithmetic number, because the mean of its divisors is an integer number (609945526).

Almost surely, 2^1219891051 is an apocalyptic number.

1219891051 is a deficient number, since it is larger than the sum of its proper divisors (1).

1219891051 is an equidigital number, since it uses as much as digits as its factorization.

1219891051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 37.

The square root of 1219891051 is about 34926.9387579272. The cubic root of 1219891051 is about 1068.4979217579.

The spelling of 1219891051 in words is "one billion, two hundred nineteen million, eight hundred ninety-one thousand, fifty-one".