1264287981 has 12 divisors (see below), whose sum is σ = 1852896416. Its totient is φ = 766234920.

The previous prime is 1264287961. The next prime is 1264287991. The reversal of 1264287981 is 1897824621.

It is a happy number.

1264287981 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1264287981 - 2⁷ = 1264287853 is a prime.

It is a super-2 number, since 2×1264287981² = 3196848197802112722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1264287981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1264287901) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1741081 + ... + 1741806.

Almost surely, 2^1264287981 is an apocalyptic number.

1264287981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1264287981 is a deficient number, since it is larger than the sum of its proper divisors (588608435).

1264287981 is a wasteful number, since it uses less digits than its factorization.

1264287981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3482912 (or 3482901 counting only the distinct ones).

The product of its digits is 387072, while the sum is 48.

The square root of 1264287981 is about 35556.8274878398. The cubic root of 1264287981 is about 1081.3061417785.

The spelling of 1264287981 in words is "one billion, two hundred sixty-four million, two hundred eighty-seven thousand, nine hundred eighty-one".