121857631 has 8 divisors (see below), whose sum is σ = 139797504. Its totient is φ = 104050680.

The previous prime is 121857629. The next prime is 121857689. The reversal of 121857631 is 136758121.

It is a happy number.

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 121857631 - 2¹ = 121857629 is a prime.

It is a super-2 number, since 2×121857631² = 29698564465864322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121857601) 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, 31255 + ... + 34936.

It is an arithmetic number, because the mean of its divisors is an integer number (17474688).

Almost surely, 2^121857631 is an apocalyptic number.

121857631 is a deficient number, since it is larger than the sum of its proper divisors (17939873).

121857631 is an equidigital number, since it uses as much as digits as its factorization.

121857631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66461.

The product of its digits is 10080, while the sum is 34.

The square root of 121857631 is about 11038.9143940879. The cubic root of 121857631 is about 495.7745666827.

The spelling of 121857631 in words is "one hundred twenty-one million, eight hundred fifty-seven thousand, six hundred thirty-one".