2154501778 has 16 divisors (see below), whose sum is σ = 3796744896. Its totient is φ = 903986640.

The previous prime is 2154501763. The next prime is 2154501809. The reversal of 2154501778 is 8771054512.

It is a super-2 number, since 2×2154501778² = 9283755822810322568, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2154501778.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3766326 + ... + 3766897.

It is an arithmetic number, because the mean of its divisors is an integer number (237296556).

Almost surely, 2^2154501778 is an apocalyptic number.

2154501778 is a deficient number, since it is larger than the sum of its proper divisors (1642243118).

2154501778 is a wasteful number, since it uses less digits than its factorization.

2154501778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7533249.

The product of its (nonzero) digits is 78400, while the sum is 40.

The square root of 2154501778 is about 46416.6110137308. The cubic root of 2154501778 is about 1291.5630709358.

The spelling of 2154501778 in words is "two billion, one hundred fifty-four million, five hundred one thousand, seven hundred seventy-eight".