21155376446 has 4 divisors (see below), whose sum is σ = 31733064672. Its totient is φ = 10577688222.

The previous prime is 21155376443. The next prime is 21155376503. The reversal of 21155376446 is 64467355112.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 21155376397 and 21155376406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155376443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5288844110 + ... + 5288844113.

It is an arithmetic number, because the mean of its divisors is an integer number (7933266168).

Almost surely, 2^21155376446 is an apocalyptic number.

21155376446 is a deficient number, since it is larger than the sum of its proper divisors (10577688226).

21155376446 is a wasteful number, since it uses less digits than its factorization.

21155376446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10577688225.

The product of its digits is 604800, while the sum is 44.

The spelling of 21155376446 in words is "twenty-one billion, one hundred fifty-five million, three hundred seventy-six thousand, four hundred forty-six".