3991023157 has 16 divisors (see below), whose sum is σ = 4402771200. Its totient is φ = 3587584000.

The previous prime is 3991023151. The next prime is 3991023217. The reversal of 3991023157 is 7513201993.

It is not a de Polignac number, because 3991023157 - 2¹¹ = 3991021109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3991023151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 554532 + ... + 561682.

It is an arithmetic number, because the mean of its divisors is an integer number (275173200).

Almost surely, 2^3991023157 is an apocalyptic number.

It is an amenable number.

3991023157 is a deficient number, since it is larger than the sum of its proper divisors (411748043).

3991023157 is a wasteful number, since it uses less digits than its factorization.

3991023157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7724.

The product of its (nonzero) digits is 51030, while the sum is 40.

The square root of 3991023157 is about 63174.5451665463. The cubic root of 3991023157 is about 1586.2126750331.

The spelling of 3991023157 in words is "three billion, nine hundred ninety-one million, twenty-three thousand, one hundred fifty-seven".