11721619 has 16 divisors (see below), whose sum is σ = 15277248. Its totient is φ = 8727552.

The previous prime is 11721607. The next prime is 11721623. The reversal of 11721619 is 91612711.

It is a cyclic number.

It is not a de Polignac number, because 11721619 - 2⁵ = 11721587 is a prime.

It is a super-2 number, since 2×11721619² = 274792703962322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11721629) 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, 2242 + ... + 5335.

It is an arithmetic number, because the mean of its divisors is an integer number (954828).

Almost surely, 2^11721619 is an apocalyptic number.

11721619 is a deficient number, since it is larger than the sum of its proper divisors (3555629).

11721619 is a wasteful number, since it uses less digits than its factorization.

11721619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7614.

The product of its digits is 756, while the sum is 28.

The square root of 11721619 is about 3423.6850030340. The cubic root of 11721619 is about 227.1586088368.

It can be divided in two parts, 117 and 21619, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 11721619 in words is "eleven million, seven hundred twenty-one thousand, six hundred nineteen".