19561420 has 12 divisors (see below), whose sum is σ = 41079024. Its totient is φ = 7824560.

The previous prime is 19561417. The next prime is 19561439. The reversal of 19561420 is 2416591.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 489016 + ... + 489055.

It is an arithmetic number, because the mean of its divisors is an integer number (3423252).

Almost surely, 2^19561420 is an apocalyptic number.

19561420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19561420 is an abundant number, since it is smaller than the sum of its proper divisors (21517604).

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

19561420 is a wasteful number, since it uses less digits than its factorization.

19561420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 978080 (or 978078 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 19561420 is about 4422.8294111349. The cubic root of 19561420 is about 269.4429300781.

The spelling of 19561420 in words is "nineteen million, five hundred sixty-one thousand, four hundred twenty".