21194126421 has 8 divisors (see below), whose sum is σ = 30432591840. Its totient is φ = 13042539312.

The previous prime is 21194126417. The next prime is 21194126449. The reversal of 21194126421 is 12462149112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21194126421 - 2² = 21194126417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21194126021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 271719531 + ... + 271719608.

It is an arithmetic number, because the mean of its divisors is an integer number (3804073980).

Almost surely, 2^21194126421 is an apocalyptic number.

It is an amenable number.

21194126421 is a deficient number, since it is larger than the sum of its proper divisors (9238465419).

21194126421 is a wasteful number, since it uses less digits than its factorization.

21194126421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543439155.

The product of its digits is 6912, while the sum is 33.

The spelling of 21194126421 in words is "twenty-one billion, one hundred ninety-four million, one hundred twenty-six thousand, four hundred twenty-one".