1651340681 has 4 divisors (see below), whose sum is σ = 1662276864. Its totient is φ = 1640404500.

The previous prime is 1651340671. The next prime is 1651340753. The reversal of 1651340681 is 1860431561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1651340681 is a prime.

It is a super-2 number, since 2×1651340681² = 5453852089451087522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1651340671) 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, 5467865 + ... + 5468166.

It is an arithmetic number, because the mean of its divisors is an integer number (415569216).

Almost surely, 2^1651340681 is an apocalyptic number.

It is an amenable number.

1651340681 is a deficient number, since it is larger than the sum of its proper divisors (10936183).

1651340681 is a wasteful number, since it uses less digits than its factorization.

1651340681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10936182.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 1651340681 is about 40636.6913146235. The cubic root of 1651340681 is about 1181.9857116658.

The spelling of 1651340681 in words is "one billion, six hundred fifty-one million, three hundred forty thousand, six hundred eighty-one".