1226616021 has 8 divisors (see below), whose sum is σ = 1817208960. Its totient is φ = 817743996.

The previous prime is 1226616019. The next prime is 1226616031. The reversal of 1226616021 is 1206166221.

1226616021 is a `hidden beast` number, since 1 + 2 + 26 + 616 + 0 + 21 = 666.

It is not a de Polignac number, because 1226616021 - 2¹ = 1226616019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 45430223 = 1226616021 / (1 + 2 + 2 + 6 + 6 + 1 + 6 + 0 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1226616031) 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, 22715085 + ... + 22715138.

It is an arithmetic number, because the mean of its divisors is an integer number (227151120).

Almost surely, 2^1226616021 is an apocalyptic number.

It is an amenable number.

1226616021 is a deficient number, since it is larger than the sum of its proper divisors (590592939).

1226616021 is an equidigital number, since it uses as much as digits as its factorization.

1226616021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45430232 (or 45430226 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 1226616021 is about 35023.0784055314. The cubic root of 1226616021 is about 1070.4577832704.

The spelling of 1226616021 in words is "one billion, two hundred twenty-six million, six hundred sixteen thousand, twenty-one".