1228739639 has 4 divisors (see below), whose sum is σ = 1240905480. Its totient is φ = 1216573800.

The previous prime is 1228739581. The next prime is 1228739641. The reversal of 1228739639 is 9369378221.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1228739639 - 2⁸ = 1228739383 is a prime.

It is a super-2 number, since 2×1228739639² = 3019602200899700642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1228799639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6082769 + ... + 6082970.

It is an arithmetic number, because the mean of its divisors is an integer number (310226370).

Almost surely, 2^1228739639 is an apocalyptic number.

1228739639 is a deficient number, since it is larger than the sum of its proper divisors (12165841).

1228739639 is a wasteful number, since it uses less digits than its factorization.

1228739639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12165840.

The product of its digits is 979776, while the sum is 50.

The square root of 1228739639 is about 35053.3827040986. The cubic root of 1228739639 is about 1071.0751818051.

The spelling of 1228739639 in words is "one billion, two hundred twenty-eight million, seven hundred thirty-nine thousand, six hundred thirty-nine".