401997851 has 8 divisors (see below), whose sum is σ = 404953680. Its totient is φ = 399049632.

The previous prime is 401997769. The next prime is 401997917. The reversal of 401997851 is 158799104.

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 401997851 - 2²⁶ = 334888987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401997451) 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, 142016 + ... + 144818.

It is an arithmetic number, because the mean of its divisors is an integer number (50619210).

Almost surely, 2^401997851 is an apocalyptic number.

401997851 is a deficient number, since it is larger than the sum of its proper divisors (2955829).

401997851 is a wasteful number, since it uses less digits than its factorization.

401997851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3805.

The product of its (nonzero) digits is 90720, while the sum is 44.

The square root of 401997851 is about 20049.8840645027. The cubic root of 401997851 is about 738.0309540903.

The spelling of 401997851 in words is "four hundred one million, nine hundred ninety-seven thousand, eight hundred fifty-one".