1029399440 has 20 divisors (see below), whose sum is σ = 2393353884. Its totient is φ = 411759744.

The previous prime is 1029399433. The next prime is 1029399451. The reversal of 1029399440 is 449939201.

It can be written as a sum of positive squares in 2 ways, for example, as 366645904 + 662753536 = 19148^2 + 25744^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-4 number, since 4×1029399440⁴ (a number of 37 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6433667 + ... + 6433826.

Almost surely, 2^1029399440 is an apocalyptic number.

1029399440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1029399440 is an abundant number, since it is smaller than the sum of its proper divisors (1363954444).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1029399440 is a wasteful number, since it uses less digits than its factorization.

1029399440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12867506 (or 12867500 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 41.

The square root of 1029399440 is about 32084.2553287434. The cubic root of 1029399440 is about 1009.7053154604.

The spelling of 1029399440 in words is "one billion, twenty-nine million, three hundred ninety-nine thousand, four hundred forty".