421157391 has 8 divisors (see below), whose sum is σ = 561759024. Its totient is φ = 280663680.

The previous prime is 421157389. The next prime is 421157423. The reversal of 421157391 is 193751124.

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

It is not a de Polignac number, because 421157391 - 2¹ = 421157389 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421157491) 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, 17386 + ... + 33831.

It is an arithmetic number, because the mean of its divisors is an integer number (70219878).

Almost surely, 2^421157391 is an apocalyptic number.

421157391 is a deficient number, since it is larger than the sum of its proper divisors (140601633).

421157391 is a wasteful number, since it uses less digits than its factorization.

421157391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53961.

The product of its digits is 7560, while the sum is 33.

The square root of 421157391 is about 20522.1195542761. The cubic root of 421157391 is about 749.5745088776.

The spelling of 421157391 in words is "four hundred twenty-one million, one hundred fifty-seven thousand, three hundred ninety-one".