10019991 has 8 divisors (see below), whose sum is σ = 13374720. Its totient is φ = 6672632.

The previous prime is 10019983. The next prime is 10020013. The reversal of 10019991 is 19991001.

10019991 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 10019991 - 2³ = 10019983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10019941) 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, 3826 + ... + 5888.

It is an arithmetic number, because the mean of its divisors is an integer number (1671840).

Almost surely, 2^10019991 is an apocalyptic number.

10019991 is a deficient number, since it is larger than the sum of its proper divisors (3354729).

10019991 is a wasteful number, since it uses less digits than its factorization.

10019991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3685.

The product of its (nonzero) digits is 729, while the sum is 30.

The square root of 10019991 is about 3165.4369366645. The cubic root of 10019991 is about 215.5869377891.

The spelling of 10019991 in words is "ten million, nineteen thousand, nine hundred ninety-one".