1551945250691 has 8 divisors (see below), whose sum is σ = 1693126239168. Its totient is φ = 1410780105000.

The previous prime is 1551945250637. The next prime is 1551945250703. The reversal of 1551945250691 is 1960525491551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1551945250691 is a prime.

It is a super-2 number, since 2×1551945250691² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1551945240691) 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, 3755405 + ... + 4148126.

It is an arithmetic number, because the mean of its divisors is an integer number (211640779896).

Almost surely, 2^{1551945250691} is an apocalyptic number.

1551945250691 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1551945250691 is a deficient number, since it is larger than the sum of its proper divisors (141180988477).

1551945250691 is a wasteful number, since it uses less digits than its factorization.

1551945250691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7921393.

The product of its (nonzero) digits is 2430000, while the sum is 53.

The spelling of 1551945250691 in words is "one trillion, five hundred fifty-one billion, nine hundred forty-five million, two hundred fifty thousand, six hundred ninety-one".