390997440 has 168 divisors, whose sum is σ = 1356725760. Its totient is φ = 103348224.

The previous prime is 390997429. The next prime is 390997457. The reversal of 390997440 is 44799093.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 365226 + ... + 366294.

Almost surely, 2^390997440 is an apocalyptic number.

390997440 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 390997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (678362880).

390997440 is an abundant number, since it is smaller than the sum of its proper divisors (965728320).

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

390997440 is a wasteful number, since it uses less digits than its factorization.

390997440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1219 (or 1206 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 390997440 is about 19773.6552007968. The cubic root of 390997440 is about 731.2366852715.

The spelling of 390997440 in words is "three hundred ninety million, nine hundred ninety-seven thousand, four hundred forty".