19621045961 has 16 divisors (see below), whose sum is σ = 21867356160. Its totient is φ = 17452081680.

The previous prime is 19621045949. The next prime is 19621045963. The reversal of 19621045961 is 16954012691.

It is not a de Polignac number, because 19621045961 - 2⁶ = 19621045897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19621045963) 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, 2791910 + ... + 2798928.

It is an arithmetic number, because the mean of its divisors is an integer number (1366709760).

Almost surely, 2^19621045961 is an apocalyptic number.

19621045961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

19621045961 is a deficient number, since it is larger than the sum of its proper divisors (2246310199).

19621045961 is a wasteful number, since it uses less digits than its factorization.

19621045961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12484.

The product of its (nonzero) digits is 116640, while the sum is 44.

The spelling of 19621045961 in words is "nineteen billion, six hundred twenty-one million, forty-five thousand, nine hundred sixty-one".