19121964 has 12 divisors (see below), whose sum is σ = 44617944. Its totient is φ = 6373984.

The previous prime is 19121953. The next prime is 19121969. The reversal of 19121964 is 46912191.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (19121969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 796737 + ... + 796760.

It is an arithmetic number, because the mean of its divisors is an integer number (3718162).

Almost surely, 2^19121964 is an apocalyptic number.

It is an amenable number.

19121964 is an abundant number, since it is smaller than the sum of its proper divisors (25495980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19121964 is a wasteful number, since it uses less digits than its factorization.

19121964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593504 (or 1593502 counting only the distinct ones).

The product of its digits is 3888, while the sum is 33.

The square root of 19121964 is about 4372.8667942209. The cubic root of 19121964 is about 267.4099105601.

It can be divided in two parts, 191 and 21964, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 19121964 in words is "nineteen million, one hundred twenty-one thousand, nine hundred sixty-four".