1221106478 has 32 divisors (see below), whose sum is σ = 2039558400. Its totient is φ = 545662656.

The previous prime is 1221106457. The next prime is 1221106489. The reversal of 1221106478 is 8746011221.

It is a happy number.

It is a super-2 number, since 2×1221106478² = 2982202061227128968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54233 + ... + 73371.

It is an arithmetic number, because the mean of its divisors is an integer number (63736200).

Almost surely, 2^1221106478 is an apocalyptic number.

1221106478 is a deficient number, since it is larger than the sum of its proper divisors (818451922).

1221106478 is a wasteful number, since it uses less digits than its factorization.

1221106478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19256.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 1221106478 is about 34944.3339899332. Note that the first 3 decimals coincide. The cubic root of 1221106478 is about 1068.8526665939.

Adding to 1221106478 its reverse (8746011221), we get a palindrome (9967117699).

The spelling of 1221106478 in words is "one billion, two hundred twenty-one million, one hundred six thousand, four hundred seventy-eight".