1651605660 has 48 divisors (see below), whose sum is σ = 5138330400. Its totient is φ = 440428032.

The previous prime is 1651605653. The next prime is 1651605671. The reversal of 1651605660 is 665061561.

It is a super-2 number, since 2×1651605660² = 5455602512288071200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1528725 + ... + 1529804.

It is an arithmetic number, because the mean of its divisors is an integer number (107048550).

Almost surely, 2^1651605660 is an apocalyptic number.

1651605660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1651605660 is an abundant number, since it is smaller than the sum of its proper divisors (3486724740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1651605660 is a wasteful number, since it uses less digits than its factorization.

1651605660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3058547 (or 3058539 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 1651605660 is about 40639.9515255616. The cubic root of 1651605660 is about 1182.0489299232.

It can be divided in two parts, 165160 and 5660, that added together give a triangular number (170820 = T₅₈₄).

The spelling of 1651605660 in words is "one billion, six hundred fifty-one million, six hundred five thousand, six hundred sixty".