917131961 has 2 divisors, whose sum is σ = 917131962. Its totient is φ = 917131960.

The previous prime is 917131949. The next prime is 917131973. The reversal of 917131961 is 169131719.

It is a balanced prime because it is at equal distance from previous prime (917131949) and next prime (917131973).

It can be written as a sum of positive squares in only one way, i.e., 648007936 + 269124025 = 25456^2 + 16405^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-917131961 is a prime.

It is a super-2 number, since 2×917131961² = 1682262067775411042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (917139961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 458565980 + 458565981.

It is an arithmetic number, because the mean of its divisors is an integer number (458565981).

Almost surely, 2^917131961 is an apocalyptic number.

917131961 is the 13544-th centered decagonal number.

It is an amenable number.

917131961 is a deficient number, since it is larger than the sum of its proper divisors (1).

917131961 is an equidigital number, since it uses as much as digits as its factorization.

917131961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10206, while the sum is 38.

The square root of 917131961 is about 30284.1866491408. The cubic root of 917131961 is about 971.5771137810.

The spelling of 917131961 in words is "nine hundred seventeen million, one hundred thirty-one thousand, nine hundred sixty-one".