19900730 has 16 divisors (see below), whose sum is σ = 35893800. Its totient is φ = 7944192.

The previous prime is 19900723. The next prime is 19900739. The reversal of 19900730 is 3700991.

It can be written as a sum of positive squares in 4 ways, for example, as 15832441 + 4068289 = 3979^2 + 2017^2 .

It is a junction number, because it is equal to n+sod(n) for n = 19900693 and 19900702.

It is not an unprimeable number, because it can be changed into a prime (19900739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4046 + ... + 7494.

Almost surely, 2^19900730 is an apocalyptic number.

19900730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19900730 is a deficient number, since it is larger than the sum of its proper divisors (15993070).

19900730 is a wasteful number, since it uses less digits than its factorization.

19900730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4033.

The product of its (nonzero) digits is 1701, while the sum is 29.

The square root of 19900730 is about 4461.0234251795. The cubic root of 19900730 is about 270.9919161725.

The spelling of 19900730 in words is "nineteen million, nine hundred thousand, seven hundred thirty".