400689421440 has 1024 divisors, whose sum is σ = 1634518241280. Its totient is φ = 81086054400.

The previous prime is 400689421411. The next prime is 400689421469. The reversal of 400689421440 is 44124986004.

It is an interprime number because it is at equal distance from previous prime (400689421411) and next prime (400689421469).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 400689421392 and 400689421401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1415863539 + ... + 1415863821.

It is an arithmetic number, because the mean of its divisors is an integer number (1596209220).

Almost surely, 2^400689421440 is an apocalyptic number.

400689421440 is a gapful number since it is divisible by the number (40) 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 400689421440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (817259120640).

400689421440 is an abundant number, since it is smaller than the sum of its proper divisors (1233828819840).

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

400689421440 is a wasteful number, since it uses less digits than its factorization.

400689421440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 42.

The spelling of 400689421440 in words is "four hundred billion, six hundred eighty-nine million, four hundred twenty-one thousand, four hundred forty".