19400990400 has 840 divisors, whose sum is σ = 80488657920. Its totient is φ = 4541184000.

The previous prime is 19400990351. The next prime is 19400990471. The reversal of 19400990400 is 409900491.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 44193381 + ... + 44193819.

Almost surely, 2^19400990400 is an apocalyptic number.

19400990400 is a gapful number since it is divisible by the number (10) 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 19400990400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40244328960).

19400990400 is an abundant number, since it is smaller than the sum of its proper divisors (61087667520).

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

19400990400 is a wasteful number, since it uses less digits than its factorization.

19400990400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515 (or 491 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The spelling of 19400990400 in words is "nineteen billion, four hundred million, nine hundred ninety thousand, four hundred".