1221938494 has 16 divisors (see below), whose sum is σ = 2118290400. Its totient is φ = 517803264.

The previous prime is 1221938491. The next prime is 1221938521. The reversal of 1221938494 is 4948391221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221938494.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221938491) 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, 489099 + ... + 491590.

It is an arithmetic number, because the mean of its divisors is an integer number (132393150).

Almost surely, 2^1221938494 is an apocalyptic number.

1221938494 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1221938494 is a deficient number, since it is larger than the sum of its proper divisors (896351906).

1221938494 is an equidigital number, since it uses as much as digits as its factorization.

1221938494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980787.

The product of its digits is 124416, while the sum is 43.

The square root of 1221938494 is about 34956.2368397973. The cubic root of 1221938494 is about 1069.0953701401.

The spelling of 1221938494 in words is "one billion, two hundred twenty-one million, nine hundred thirty-eight thousand, four hundred ninety-four".