21405151246 has 8 divisors (see below), whose sum is σ = 32360544000. Its totient is φ = 10618303248.

The previous prime is 21405151241. The next prime is 21405151247. The reversal of 21405151246 is 64215150412.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21405151241) 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, 42135871 + ... + 42136378.

It is an arithmetic number, because the mean of its divisors is an integer number (4045068000).

Almost surely, 2^21405151246 is an apocalyptic number.

21405151246 is a deficient number, since it is larger than the sum of its proper divisors (10955392754).

21405151246 is a wasteful number, since it uses less digits than its factorization.

21405151246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84272378.

The product of its (nonzero) digits is 9600, while the sum is 31.

The spelling of 21405151246 in words is "twenty-one billion, four hundred five million, one hundred fifty-one thousand, two hundred forty-six".