398634157 has 4 divisors (see below), whose sum is σ = 399891996. Its totient is φ = 397376320.

The previous prime is 398634133. The next prime is 398634199. The reversal of 398634157 is 751436893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 62315236 + 336318921 = 7894^2 + 18339^2 .

It is a cyclic number.

It is not a de Polignac number, because 398634157 - 2¹¹ = 398632109 is a prime.

It is a super-3 number, since 3×398634157³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398634107) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 628444 + ... + 629077.

It is an arithmetic number, because the mean of its divisors is an integer number (99972999).

Almost surely, 2^398634157 is an apocalyptic number.

It is an amenable number.

398634157 is a deficient number, since it is larger than the sum of its proper divisors (1257839).

398634157 is a wasteful number, since it uses less digits than its factorization.

398634157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1257838.

The product of its digits is 544320, while the sum is 46.

The square root of 398634157 is about 19965.8247262666. The cubic root of 398634157 is about 735.9667086046.

The spelling of 398634157 in words is "three hundred ninety-eight million, six hundred thirty-four thousand, one hundred fifty-seven".