1651961 has 2 divisors, whose sum is σ = 1651962. Its totient is φ = 1651960.

The previous prime is 1651943. The next prime is 1651981. The reversal of 1651961 is 1691561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1525225 + 126736 = 1235^2 + 356^2 .

It is an emirp because it is prime and its reverse (1691561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1651961 - 2¹⁰ = 1650937 is a prime.

It is a Chen prime.

It is a plaindrome in base 13.

It is not a weakly prime, because it can be changed into another prime (1651921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 825980 + 825981.

It is an arithmetic number, because the mean of its divisors is an integer number (825981).

2^1651961 is an apocalyptic number.

It is an amenable number.

1651961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1651961 is an equidigital number, since it uses as much as digits as its factorization.

1651961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1620, while the sum is 29.

The square root of 1651961 is about 1285.2863494179. The cubic root of 1651961 is about 118.2133695748.

The spelling of 1651961 in words is "one million, six hundred fifty-one thousand, nine hundred sixty-one".