1231965428 has 6 divisors (see below), whose sum is σ = 2155939506. Its totient is φ = 615982712.

The previous prime is 1231965409. The next prime is 1231965439. The reversal of 1231965428 is 8245691321.

It can be written as a sum of positive squares in only one way, i.e., 631617424 + 600348004 = 25132^2 + 24502^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 153995675 + ... + 153995682.

It is an arithmetic number, because the mean of its divisors is an integer number (359323251).

Almost surely, 2^1231965428 is an apocalyptic number.

It is an amenable number.

1231965428 is a deficient number, since it is larger than the sum of its proper divisors (923974078).

1231965428 is a wasteful number, since it uses less digits than its factorization.

1231965428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307991361 (or 307991359 counting only the distinct ones).

The product of its digits is 103680, while the sum is 41.

The square root of 1231965428 is about 35099.3650654823. The cubic root of 1231965428 is about 1072.0116545198.

The spelling of 1231965428 in words is "one billion, two hundred thirty-one million, nine hundred sixty-five thousand, four hundred twenty-eight".