1221677638 has 8 divisors (see below), whose sum is σ = 1842111360. Its totient is φ = 607640520.

The previous prime is 1221677629. The next prime is 1221677657. The reversal of 1221677638 is 8367761221.

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

It is a junction number, because it is equal to n+sod(n) for n = 1221677594 and 1221677603.

It is a congruent number.

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, 1598673 + ... + 1599436.

It is an arithmetic number, because the mean of its divisors is an integer number (230263920).

Almost surely, 2^1221677638 is an apocalyptic number.

1221677638 is a deficient number, since it is larger than the sum of its proper divisors (620433722).

1221677638 is a wasteful number, since it uses less digits than its factorization.

1221677638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3198302.

The product of its digits is 169344, while the sum is 43.

The square root of 1221677638 is about 34952.5054609823. The cubic root of 1221677638 is about 1069.0192888997.

The spelling of 1221677638 in words is "one billion, two hundred twenty-one million, six hundred seventy-seven thousand, six hundred thirty-eight".