19771428 has 24 divisors (see below), whose sum is σ = 47622400. Its totient is φ = 6377760.

The previous prime is 19771387. The next prime is 19771447. The reversal of 19771428 is 82417791.

It is a zygodrome in base 8.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26203 + ... + 26946.

Almost surely, 2^19771428 is an apocalyptic number.

It is an amenable number.

19771428 is an abundant number, since it is smaller than the sum of its proper divisors (27850972).

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

19771428 is a wasteful number, since it uses less digits than its factorization.

19771428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53187 (or 53185 counting only the distinct ones).

The product of its digits is 28224, while the sum is 39.

The square root of 19771428 is about 4446.5073934494. The cubic root of 19771428 is about 270.4037307061.

The spelling of 19771428 in words is "nineteen million, seven hundred seventy-one thousand, four hundred twenty-eight".