154999149481861 has 4 divisors (see below), whose sum is σ = 159999122045824. Its totient is φ = 149999176917900.

The previous prime is 154999149481849. The next prime is 154999149481871. The reversal of 154999149481861 is 168184941999451.

It is a happy number.

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 not a de Polignac number, because 154999149481861 - 2⁵ = 154999149481829 is a prime.

It is a super-2 number, since 2×154999149481861² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (154999149481801) 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, 2499986281935 + ... + 2499986281996.

It is an arithmetic number, because the mean of its divisors is an integer number (39999780511456).

Almost surely, 2^{154999149481861} is an apocalyptic number.

It is an amenable number.

154999149481861 is a deficient number, since it is larger than the sum of its proper divisors (4999972563963).

154999149481861 is an equidigital number, since it uses as much as digits as its factorization.

154999149481861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4999972563962.

The product of its digits is 806215680, while the sum is 79.

The spelling of 154999149481861 in words is "one hundred fifty-four trillion, nine hundred ninety-nine billion, one hundred forty-nine million, four hundred eighty-one thousand, eight hundred sixty-one".