20190312640 has 112 divisors (see below), whose sum is σ = 51236831232. Its totient is φ = 7560498176.

The previous prime is 20190312619. The next prime is 20190312689. The reversal of 20190312640 is 4621309102.

It is a junction number, because it is equal to n+sod(n) for n = 20190312599 and 20190312608.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 316737 + ... + 375103.

Almost surely, 2^20190312640 is an apocalyptic number.

20190312640 is a gapful number since it is divisible by the number (20) 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 20190312640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25618415616).

20190312640 is an abundant number, since it is smaller than the sum of its proper divisors (31046518592).

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

20190312640 is a wasteful number, since it uses less digits than its factorization.

20190312640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58454 (or 58444 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 28.

The spelling of 20190312640 in words is "twenty billion, one hundred ninety million, three hundred twelve thousand, six hundred forty".